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An RV for an armless pilot

Thanks for the suggestion! I might open a can of worms asking which model is better, but no one has suggested an RV-10. The range, speed, space, and capacity would let me take more people up on a discovery flight. Is the RV-10 just too complex?

Nothing at all complex about a -10. Flies the same as any RV. You know your mission better than any of us.
 
Welcome to VAF

The rudders and brakes could be a single connection to the mechanism like the VeriEze does------push a little and you get rudder. Push a lot and you also get brakes.

You still need to apply brakes individually to turn, and together to stop-----this is going to take a bit of tinkering, but no reason it cant be done.

Throttle control while taxing could be another issue all on its own. As mentioned previously, blow tube may be the answer???

By the way, Welcome aboard the good ship VAF:D:D
 
Jessica,
I trust you are okay with me posting this Inside Edition video of you in the Ercoupe. Of the several I viewed, I thought this one showed best how you expertly use your feet to control the airplane.

https://youtu.be/b2IqpPSF9-U
 
After more thought, the fly-by-wire ide would be the way to go. The hardware already exists and is available.

A set of the larger autopilot servos could do the job. Just need an interface. I bet Dynon or GRT could be talked into a simple interface. If not, I'm sure someone else is capable of creating that serial interface. A modified stick could be retained to allow manual reversion as well. That leaves the brakes and engine controls. A servo drive would work fine there as well.

I tend to agree and think these ideas could really work. Easily defeated servo controls on the throttle or brakes could work well with ground handling, and if there's any failure these can still be operated.

The Automotive world went to FBW throttles 15-20 years ago (could still install a manual control for safety/redundancy), and possibly using or modifying an automotive ABS unit for the brakes could work. The ABS unit can pressurise the brake circuit if required, or another mechanism like a foot pedal could override.

Safety, functionality, and reliability has to be considered in every step here. I'm also certain there's ways to achieve all three with careful engineering.

Finally, after watching a few of the youtube videos, it makes a lot of us "able-bodied" people look rather ordinary. Good Luck!!
 
I think the brakes are one of the easier problems to solve and has been done before. A single brake lever where the linkage is combined with the rudder. Move the rudder by itself, no brakes are applied. Move the rudder and press the lever, brakes are applied proportionally to the rudder deflection. It would take some tuning to get the ration right, but a simple mechanical linkage similar to ruddervators or flaperons.

If you go fly-by-wire for pitch and roll, the servos and mounts are available off the shelf, and you would want an AP anyway for long flights. I would simply upgrade to the larger higher torque versions of the servos. A second set of servos could be added for redundancy. Now you can place the controls wherever it is most comfortable.

A big bonus of the FBW is that you can have dual controls with a switch to disable the passenger controls in the event someone freezes. Plus you could change the control rate and null at-will to your preference.

I do really think the fly-by-wire would be the best way to go. It may sound complicated, but in reality is a very simple installation using readily available and well proven hardware. If you by and RV-10, it probably already has AP servos. Keep the existing and add a second slaved set. With that flexibility, you could keep the engine controls manual or make them electronic.

For avionics, Dynon has separate autopilot, comm, and general button remote heads, so those could be placed near the controls while the PDF/MDF is still located for best viewing.
 
Sorry to post so much, but problem solving is something I love to do.

Another suggestion:

Contact Vans and see if they are willing to provide some level of CAD model of the RV-10 cockpit and flight controls.

Contact the Embry-Riddle Aeronautical University (Prescott, AZ Campus)engineering department and tell them what you want to do. I'm sure they will jump right on it. Give the students the model and work with them on requirements and preferences. Fall Semester just started and I'm sure they will come up with some awesome ideas.

There are a number of RV builders in the area, probably some with an RV-10 that I'm sure would be willing to consult as well.
 
... I'm going to have to find an -8 to sit in before I rule it out.

The mission, as you have explained it, requires more seats, so let's focus on a -10. Nothing lost if you change your mind, as much of the mechanics would apply to other models.

I had forgotten about braking. Maybe the brakes could be left on both sides and I just let go of the stick on the ground and steer with the pedals with both feet?

Fine for taxi, not so good for landing. It would be advantageous to maintain aerodynamic control until speed had dropped below the point where it is no longer useful. Releasing the stick would compromise crosswind capability, plus switching controls takes a finite amount of time during a very busy time.

Making the jump to cross country utility will require dealing with winds and other factors you may not often face in round-the-patch flying...in particular when pressured by passenger expectations.

My first thought was a two-button electric throttle system on the stick or rudder that I could push with a toe.

Marvelous idea, and easily done. At the fundamental level, it's the same as a trim servo.

You'll need a two-axis autopilot for practical cross-country. A RV won't always stay upright when you release a primary flight control to operate a switch or device.

Do all RVs share that characteristic? :eek:

To a greater or lesser degree, yes. But hey, an RV-10 without a 2-axis autopilot would be a rare beast indeed, and the currently available AP systems bring 90% of a fly-by-wire system with them for free. A big percentage of -10 owners (heck, make that all RV owners) do their cruise flying with button and knob manipulation, not stick and rudder. In your case, I see it as a huge comfort factor. It also eliminates concern with mixture and propeller controls, as both can be positioned for cruise or landing while on autopilot.

For discussion, here's a good photo of the standard RV-10 primary flight controls, courtesy Brian Steeves.
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I had one experience helping a friend modify a Luscombe so he could fly it. He was missing one leg. We basically made the rudder system a "closed loop" where we connected the rudders with a "balance" cable that basically ran around from one pedal to the other which replaced the factory firewall return springs. We put a leather strap on the applicable rudder pedal the strap his foot in place. Then he was able to control the rudders completely by merely pushing or pulling with the same foot depending on whether or not he wanted left or right rudder input. For breaking we installed a brake cylinder similar to the Piper Tripe Acer or early Comanche that was activated with one hand lever. In your case it could be heel brake positioned on the floor similar to the ones found in cubs, Aeroncas, Taylorcrafts and Luscombes.

I like this idea. Your brainstorming helps drive new ideas. Thanks for the suggestion.

I’m wondering if the control stick could be positioned in such a way as to leave access to both rudder pedals. That would eliminate reworking the breaks/ground steering. That may just come down to the space available in whichever airplane I choose. Again, thanks to everyone! Please keep the suggestions coming!
 
Jessica,

We are all amazed at your willingness and success in mastering flight! I think that now is the time to consider new methods of control for you, rather than trying to adapt the existing control strategy in an RV. It is an opportunity for those of us interested in innovation and finding new ways to to accomplish specific tasks to get involved. For example, I recommend that you use an existing 2 seat, side by side RV to test concepts that might work. The concept is called an inflight simulator. They have been in use for a long time, and could view you as the controller, and adapt the inceptors to allow you to control the airplane in ways that suit you the best. Then when you determine what works the best, you modify your own airplane and join the RV fleet. I'll pass this along to those in the industry who may be interested.

Thank you, Terry!
Yes, prototype controls will be a must. What about building a miniature apparatus out of wood to test different setups? I wonder if it would be too hard to swap out radically different control systems directly in the airplane.

I generally like the side by side seating because it gives me more room for my knees, but with a custom setup, that might not be necessary. We will have to see how things go.
 
I'm going to go in a different direction here. I think a modified RV is doable, but like everything else, it's going to take time (probably a lot longer than anticipated if my past experience is any indication!). For now though, what about an autopilot for the Ercoupe? You flip it on and relax for the flight until it's time to join the pattern.

That would be so nice! Ercoupes aren’t known for their capacity, though. With my husband and me onboard, we can’t fill the tanks all the way up. How much would a retrofit like that weigh?
 
I would also like blending the manual flight controls with some automation. in-flight automation is probably the easiest with speech commands converted to electronic commands that may simulate an autopilot controller (Garmin 507 for example) talking to the MFD/PFD. Garmin already makes an audio panel with voice control. Why not an autopilot with voice control.

I have always wanted to add FADEC. This would be a great time to do that. Using linear actuators or stepper motors to manipulate throttle, mixture and prop, again with some type of slip clutch for an override.

All the switches could be digital switches or controlled by a digital relay taking a voice command or some type of mouth or head movement command.

How can we make this conversation turn into a well run project?. I am an engineer but we will need PMs to keep us on track. I am confident many people on this forum will contribute with their skills when asked. There are so many amazing people on this forum.

I may need to see exactly what your suggestions are in the real world but I appreciate your emphasis on safety!

There’s certainly a lot to be worked out! My first goal is to choose an airplane that can be modified, then try to raise the funds to get it, then I’ll definitely need the help delegating all the little bits that need to be done!

Thanks for the suggestions!
 
The fly-by-wire concept is interesting, but it seems it would need to be a redundant system, in case a servo were to fail. A friend had his roll servo fail in flight the other day in his RV-10; not a real problem for an airplane with mechanical linkages, but disastrous in a true fly-by-wire system without reversion to mechanical or redundant electrical or vacuum controls.

I'd stick with mechanical controls, but of course add an autopilot for convenience and safety.

I wonder if there are any project airplanes languishing out there that are close to the quick-build stage of fuselage completion? It would offer a good test bed for controls mods. An owner of such a project who couldn't complete it might donate it to Jessica's foundation, which is a 501(c)3
 
Jessica,
Agree with a few of the others on the post that a 9A would be a great platform. The controls are so much more forgiving than any other model, except maybe the 10. The 9 has so much rudder surface area and overall authority that with the right modifications you would need little input on a nice flying day. For those gusty x-wind days you could easily get the authority you need without much effort.

Along with the control modifications, I would also research the idea of modifying the panel layout to move forward / after and height to optimize for your seating position.

Also would recommend looking at the slider vs. the tip-up and how it will be for managing you entry / exit. The slider has options which may help with the seat position over the tip-up too which is something else to consider.

I am in south Phoenix and would love to see how I can also assist in your RV adventure. Being without a plane as I transition to my next project, I am eager to chat or be put to work on some sort of project! I have watch your flying career with such admiration. The people and resources in the Vans community is second to none!

Feel free to PM me anytime for my contact information.
 
Controls For RVS

Ok Vans Aircraft. I know you watch this forum. So you engineers get your heads together and help this lady out. I know you guys can do it. It would be cool if you did.
 
Now we are talking . . .

Hi Jessica,

I work at Apple and have worked closely with the Accessibility team. We always start with a clear understanding of the user's abilities before designing a system to accommodate them. Given that, I'd like to understand what motions or manipulations you would be prefer to use for aircraft control and your relative strength and precision for each motion.

1. Pushing and pulling your feet
2. Moving your knees from side to side.
3. Rocking your feet forward (like pushing a gas pedal) or backward.
4. Twisting your feet left and right (around an axis through your lower leg).
5. Gripping or manipulating controls with your toes.
6. Mouth controls (blow/suck tube)
7. Any upper torso motion?
8. Anything I'm missing?

Once we know which motions you'd like to use for each aircraft control, I have no doubt that this group has the brain power to come up with the modifications necessary to give you that control.

I'd be happy to help in any way I can; I'm close enough to fly down if necessary.

The mechanisms can be adapted and fit just about anywhere, but I bet you have the best ideas about a desirable interface. This group can make that a reality. I am afraid I have no clue what forces, movement, digit dexterity abilities are needed to do all the functions.

There are the basic controls, pitch, roll, rudder, but there are engine controls, and radios that come into play.

Help the VAF team generate some ideas to meet some specific needs!!

I, for one, am looking forward to progressing with (and learning from) your challenge to the group.
 
Since, like most Ercoupes with Stromburgs, there is only a single throttle power control on the 912- got to thinking when I saw above-

Could not a one-off ish RV-12 mimic the Ercoupe? Reduce crosswinds and aft gear reset to landing crabbed like a no rudder pedal ercoupe.

Link rudders to nose gear directly, not free castoring- like a Rocket link tailwheel.

Brakes, like a Sonex- one motion, shared cylinder to both pistons.

Pitch trim/flaps- is the 12 pitchy at flap extension/retraction?

Is the gain vs Ercoupe by mirroring it with a -12 worth the gains or is a 9A more the target, done similarly?

From one of the guys leaving in the C-17 at KOSH'12 Jessica waved at.
 
Since, like most Ercoupes with Stromburgs, there is only a single throttle power control on the 912- got to thinking when I saw above-

Could not a one-off ish RV-12 mimic the Ercoupe? Reduce crosswinds and aft gear reset to landing crabbed like a no rudder pedal ercoupe.

Link rudders to nose gear directly, not free castoring- like a Rocket link tailwheel.

Brakes, like a Sonex- one motion, shared cylinder to both pistons.

Pitch trim/flaps- is the 12 pitchy at flap extension/retraction?

Is the gain vs Ercoupe by mirroring it with a -12 worth the gains or is a 9A more the target, done similarly?

From one of the guys leaving in the C-17 at KOSH'12 Jessica waved at.

Her stated mission dictates a 4 seat hauler (rv10). Anything less sounds like it wouldn't complete the mission.
 
OK, same thing- scale the Ercoupe up to RV10. If a yoke works, lower it/reset for comfort. Folks replace Swift yokes with stick retrofits- reverse it.

Aft gear set for crabbed landings in crosswinds, single brake control, direct nose steering.

Pitch trim /flap link/rate/deflection matching.
 
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Lots of good suggestions so far, but at this point they're all just kinda shots in the dark. The apple guy is asking some of the right questions to get started in defining what is/isn't a possible solution. I didn't see anywhere in the thread the other half of the requirements question, and that is, what are you legally allowed to fly per your license restriction? Does it currently say just an ercoup or are you restricted to anything that links rudder and aileron controls? Are you willing to deal with the FAA to expand your restrictions or would you like a solution that fits inside your current allowables? Gotta define the system level requirements before you start creating the technical solution.
 
Jessica,
Plenty of motivated experimenters here to help, but likely few of us understand your unique capability. Would be great to understand these things better:
Hi Jessica,

I'd like to understand what motions or manipulations you would be prefer to use for aircraft control and your relative strength and precision for each motion.

1. Pushing and pulling your feet
2. Moving your knees from side to side.
3. Rocking your feet forward (like pushing a gas pedal) or backward.
4. Twisting your feet left and right (around an axis through your lower leg).
5. Gripping or manipulating controls with your toes.
6. Mouth controls (blow/suck tube)
7. Any upper torso motion?
8. Anything I'm missing?

The idea below is close to my first thought which would be to use an oversized “Track ball” (maybe 6” radius?) implementing 3 axis control. Roll the ball Fore-Aft for elevator, Right-Left for aileron, and Twist at the ankle for yaw. We might find enough mechanical advantage to do this manually if you have sufficient strength. Alternatively we go digital and just use this as an input control using autopilot servos for actuation. Other foot available for a pedal throttle and brakes like a car.

Remainder of switches, controls resized and relocated to the floor for foot operation (flaps, lights, ignition, starter, etc). Fuel selector also on the floor.

Should allow a normal upright seating position with normal rest positions for hips, knee, and ankle.

How about a boot to fit your feat in. Twist for rudder, for and aft for elevators, right and left for ailerons. That would leave the Other foot/leg for throttle, flaps, and brakes. Changing radios etc by voice command. That way she would have a more comfortable seating position. Also I think the 8a would be the ezest to modify. Entry/egress I think you already have a handle on. Wish I had more resources to offer, but if there’s anyway I can help feel free to ask. Good luck on this project I’m shure someone with your tenacity will get it don.

Perhaps a purpose made shoe would ease operation of the “track ball”. Here’s another similar idea.

I really like the idea of a boot that would allow you to use what is essentially a three-axis joy stick. We use that type of roll/pitch/yaw hand controller in spacecraft, and it is very natural - assuming you can get the mechanical leverage you need.

Paul

Finally, if you have adequate fine motor control, two small joy sticks have been used to fly R/C aircraft for decades. They could be floor mounted and Would operate autopilot servos (plenty of folks here who could make that happen).

Thanks for checking in. Exactly the sort of challenge that gets us excited. Let’s make it happen!

Peter
 
What about the heel controlling the rudders

Traditional airplane controls have the brakes and rudder combined into rudder pedals. As mentioned before the brakes can be separated from the rudder pedals and solved separately from the rudder. So, I will focus on just the rudder. Others have mentioned having a boot or strap type connection to operate the stick. That solves operating the elevators and ailerons. However, what if it was more like a slipper with sides at the heel. The heel could be used to control the rudders by swinging the heel back and forth and would be fly by wire with feedback. This seems like it would be a very natural and intuitive control. In addition, at the top of the slipper, there could be a hat control or other buttons to control other functions. The stick could also be moved to make it more comfortable.

Just a thought.

Dave Syvertson
RV-10
 
Jessica,

Would it be possible for you to post a list of absolute requirements, followed by strong preferences, followed by "nice-to-haves?"

That might help nudge the discussion into some very productive paths.

For instance, if you really want cargo and passenger capability, an RV-10 might become a "must."

Maybe the list could be further broken down as to:

Flight controls location
Engine controls type
Avionics interface
Cabin/cargo capacity/features/creature comforts
 
Having flown both an Ercoupe and most of the two-seat RV's, but not a -10, i'm thinking that any of these could be handled on the ground and flown quite easily. What concerns me is the other bit... Taking off and landing.

An Ercoupe is flown onto the ground in a manner akin to landing on a carrier... You just plant it on the runway. Once it's on, regardless of crab angle, it self-straightens (bet the F-14's wish that was possible!) and steering continues with the same control you used for flying... the yoke.

The RV's need significantly more finesse on the rudder for slip and crosswind correction. So any system will need to give Jessica the capability to manipulate both at the same time, and Jessica will need to (quoting an old instructor I knew) "learn what her feet are for."(*)

(* Jessica, if you haven't heard the expression, it's used to describe someone who has only ever flown airplanes where rudder use isn't really necessary most of the time... Like an Ercoupe or Cessna 172... Students with all of their limbs frequently don't really learn (or very quickly forget) how to use a rudder until they get into a plane where it's not an option.)
 
Reducing workload

Hi Jessica,

I'm trying to think outside the box a little. How about a rudder bar with brakes on top of a short control stick. 'rotate' for rudder, tilt for aileron, push / pull for elevator.

Maybe the brakes are combined with the rudder bar, the more rudder you apply the more left/right brakes for a castor nose wheel.

A little off your original question but a couple of other ideas:

1) A GTN750 radio and GMC 35C audio panel have a large number of voice commands that will reduce the need for touching small buttons
2) A power system like the Vertical Power series can be programmed to set the electrics (flaps, fuel pumps, lights etc.) according to the phase of flight.

Intriguing challenge, I think an RV8 might be easier to modify with your custom setup in the front and a regular set of controls in the back if you want / need two setups?

But side by side seating might be better for your use?

Aerodon
 
Some additional thoughts......

I think an experimental category airplane is perfect for developing systems to adapt to specific needs of particular pilots.

Like Dan, my first thought was an RV-8A but I understand the specified mission for 4 seats, AC environmental control, etc so that would mean adapting an RV-10. At first glance it seemed like it's style of control system would be more difficult but the more I think about it, if modifications could be designed to work well on the RV-8, then the RV-10 should be just as possible.

I have done a quick scan through the ideas presented so far and I think many are a good start in the thinking process.

I personally think it would be best to stay with a mechanical flight control system vs something fly by wire.
The complexity of that; not in the physical design to make something work, but in developing a robust system with the necessary redundancies that it should have along with EMI safety, etc would make the project that much more complicated in my opinion.

Moving fwd, I think it would be helpful if Jessica could describe the physical abilities and attributes that she has that are outside of what most of us would imagine.

I.E., I would guess that her leg strength (both pushing, pulling, and lateral force) is above that of the average female of her size?
I would also guess that she has a dominant foot just like people have dominant hands? This may not be a design consideration, but if it was, it would be good to know.

My initial design thoughts are that one foot (which one, might be influenced by answers to some of the above questions) would control rudder and brakes.
I'm not sure it would matter which foot but the answer to the dominant foot question may have a design influence as well as some of the other systems controls (switches, etc.). It would be push pull for the rudder and fore/aft tilt of the foot for brakes, something along the lines of a split pedal like is common on farm tractors (that I think someone already mentioned). The design challenge would be having a way to modulate between just a single wheel being braked, to both wheels and back again without having to fully release the brakes to make the switch. I think this would be an important design aspect.
This control would be the one that in particular has some type of stirrup and heal rest so that the foot could be moved from it in flight for activating electrical switches, pitch and roll trim, etc., on a control panel that was located nearby. Including a yaw damper with the auto pilot would probably be beneficial to this part of the design.

The opposite foot would control pitch and roll and would have a similar stirrup / heal rest arrangement which could allow access of some other controls during trimmed cruise flight or on auto pilot when constant control input wouldn't be needed. The actual control function could be tailored to fit Jessicas' specific foot and leg strength but my initial idea would be push for nose up and pull for nose down and twist left and right for roll. Reason being... that push for nose up would be the lowest risk off accidentally having her foot pull out of the mechanism when very low to the ground while needing to round out and flare for landing. I think it would also provide the best precision dealing with the trim change that can occur as speed dissipates in the flair. The down side to this choice is that on a balked landing / go around the high control forces that can occur with the application of full power would require a substantial pull for nose down input until the pitch trim could be readjusted more nose down.
This is one of the design aspects that I think would require a bit of careful consideration if my other ideas were used because the RV-10 in regards to power to weight ration and engine torque influence, at a low IAS with full power applied at low altitude during a go around is not going to be a good time to move a foot from the rudder control to make pitch trim adjustments. If we are honest, this is a situation that at times can be a hand full (no pun intended) for any pilot with two feet and two hands. It is flight situations like this, whether they occur only on rare occasions or not, that need to be carefully considered and designed for, if the airplane is going to be safe at all time for Jessica and any passengers she carries.

A couple of valuable parts of the design would be choosing an EFIS system that has integrated controls that could be remote mounted (near the foot pedals) and manipulated by Jessicas' toes. My first thought would be Dynon because of the multiple switch/knob modules they have available to manipulate the autopilot many of the on screen functions remotely. Other EFIS systems may work just as well but a side benefit to choosing the proper system would be full control of the system from the right seat as well. I see this as an important part of the design along with a full set of standard controls so that the airplane could be flown by other pilots. I see this as being an important part of the design because the airplane will have to have to have phase 1 flight testing done and there will be a lot of transition training for Jessica to learn to fly the RV-10 and develop the muscle memory for the non-standard control system. With proper design is would even be possible to have a paralleled electrical control system for some of the general electrical items so that a pilot who is using the standard controls position can still control all of the systems.
Other details would of course be working out details for engine control (SDS would help this a lot), propeller, avionics, environmental (heat and AC), etc.
It seems that a natural choice for throttle (and perhaps RPM) would be some type of mouth control that would move the throttle up or down at a set rate. This could be coupled into a mechanical knob system for use at the standard controls position and potentially even have it interconnected to an out of the way but easily reachable foot level that could be accessed if there was a failure of the mouth system.
Final thought -
Considering the extensive modifications that would have to be made, it might be a tossup whether it was easier to just build a new RV-10 rather than try and modify an already flying airplane... maybe not.
The up side to modifying a flying RV-10 is that someone could be paid for any or all work. If we assumed that Jessica would not build a new RV-10 herself, that would leave her having someone build it for her.
The possibly) down side of that would mean it could not be certified as experimental amateur built.
It could however be certified as experimental exhibition, which considering her intended mission, I think it fits with very well.
 
Hi Jessica,

I work at Apple and have worked closely with the Accessibility team. We always start with a clear understanding of the user's abilities before designing a system to accommodate them. Given that, I'd like to understand what motions or manipulations you would be prefer to use for aircraft control and your relative strength and precision for each motion.

1. Pushing and pulling your feet
2. Moving your knees from side to side.
3. Rocking your feet forward (like pushing a gas pedal) or backward.
4. Twisting your feet left and right (around an axis through your lower leg).
5. Gripping or manipulating controls with your toes.
6. Mouth controls (blow/suck tube)
7. Any upper torso motion?
8. Anything I'm missing?

Once we know which motions you'd like to use for each aircraft control, I have no doubt that this group has the brain power to come up with the modifications necessary to give you that control.

I'd be happy to help in any way I can; I'm close enough to fly down if necessary.

Thank you so much and these are great questions.

1) Push/pull is easy, its the mechanism that's important. A stirrup or strap would make this easiest. Grabbing a bar and pulling would be harder.

2) Knees are useful but I would worry about them affecting other controls. E.g. if I move my knee it might move my foot too if I'm holding on to something.

3) Flexing my foot forward and back is fine. I can probably flex slightly farther than most people but not by much.

4) Rotating my whole foot side to side is also doable. Again, probably more range than most people but not by a lot.

5) I can get ahold of/twist radio nobs, switches, etc. Placement would be important though.

6) Mouth control is an option but not something I'm accustomed to.

7) I have some movement of my shoulders. I've seen turn indicators on cars activated by large buttons at the shoulder. However, the one thing that has worked is the bar extensions from the handlebars on my bike allow me to steer. It is not fine-tuned control for something like the control stick but might be a more appropriate option for activating flaps or something similar.

8 A) Using my toes to rotate dials and nobs doesn't go as far as people's hands. It works best for something incremental like radios. Not something for a primary control, I would think.

8 B) I use my heel to press down on a button to shift gears on my bike. It might be better if you see what I mean: https://www.youtube.com/watch?v=bl7wNch4gC4

8 C) I can use my toes on a touch screen. (Including the fingerprint scanner on my iPhone 8 ;))

8 D) I have a strong grip between my big toe and second toe. I can also use them independently with the other toes decreasing in individual dexterity. I have enough control over my first two toes that I used to use them to put my contacts in.

8 E) There was a time I tried to use a set of buttons behind my head to control the gears on my bike. It didn't work out because I couldn't always tell which button I was pressing and I could never rest my head.

8 F) The fine motor skills and small movements of my feet are as well trained as most people's hands.
 
RV Colleagues, This is a terrific discussion, and an example of how we can brainstorm by ourselves and through industry contacts to innovate and make the RV both accessible and useful for Jessica.

It is really wonderful to have so many people willing to help. Thank you all once again!
 
I really like the idea of a boot that would allow you to use what is essentially a three-axis joy stick. We use that type of roll/pitch/yaw hand controller in spacecraft, and it is very natural - assuming you can get the mechanical leverage you need.

What a great brainstorming session!

Paul

I'm open to the boot. I will need to try a prototype to see how I feel about it. Thanks all who have suggested it.
 
Maybe I've missed it, but Jessica, have you flown an RV? If not, I would bet you could hop in just about any RV near you and fly it just fine, stock. That would at least imprint the appropriate grin to know what you're in for :).

I'm taking a look at someone's RV-10 tomorrow. :) I want to track down some of the other models, too.
 
Side to side or Heel toe

I can't relate directly but I did drive a race car several years and control of both brake and throttle with my right foot became second nature. It's called "Heel/Toe". Very common in driving. The gas is bumped before the clutch is released then applied fir power and often under the sequence is done while braking hard for a corner. Some actually use the Heel for Gas and Toe for brake. I used the ball of my foot rotating side to side. Brake and gas were adjusted so the sweet spot was even and controlling either required very little movement. It's so engrained, I drive my personal cars the same way.
I'm just throwing it out there. Jessica probably has far more ankle dexterity than most so don't get stuck on a push/ pull arrangement. She may be able to heel/toe or roll her feet and get differential braking or combined braking or even pitch and roll. Same for power and prop. Move them down where her feet are controlling the airplane.
Think outside the box.
 
The rudders and brakes could be a single connection to the mechanism like the VeriEze does------push a little and you get rudder. Push a lot and you also get brakes.

I like this idea. Could it be consolidated into a single pedal? Push forward a little for the left rudder, more for the left brake, then pull the pedal back for the right rudder, more for the right brake. Perhaps add a single bicycle brake handle to activate both breaks that I could activate by pushing it with my opposite foot.

It might mean I need a safety pilot to manage the breaks for a short runway, but maybe not with practice. My husband looks for any excuse to fly, so no big issue there. At my home airport, I could possibly land with a long ground roll (it is 4,600 ft long) to allow more time to reach for the full break handle. Is there some other safety issue I'm not considering?
 
I think the brakes are one of the easier problems to solve and has been done before. A single brake lever where the linkage is combined with the rudder. Move the rudder by itself, no brakes are applied. Move the rudder and press the lever, brakes are applied proportionally to the rudder deflection. It would take some tuning to get the ration right, but a simple mechanical linkage similar to ruddervators or flaperons.

If you go fly-by-wire for pitch and roll, the servos and mounts are available off the shelf, and you would want an AP anyway for long flights. I would simply upgrade to the larger higher torque versions of the servos. A second set of servos could be added for redundancy. Now you can place the controls wherever it is most comfortable.

A big bonus of the FBW is that you can have dual controls with a switch to disable the passenger controls in the event someone freezes. Plus you could change the control rate and null at-will to your preference.

I do really think the fly-by-wire would be the best way to go. It may sound complicated, but in reality is a very simple installation using readily available and well proven hardware. If you by and RV-10, it probably already has AP servos. Keep the existing and add a second slaved set. With that flexibility, you could keep the engine controls manual or make them electronic.

For avionics, Dynon has separate autopilot, comm, and general button remote heads, so those could be placed near the controls while the PDF/MDF is still located for best viewing.

Colin, you make this sound very doable. Thank you. Fly by wire looks like a point of debate but I like what you said about being able to disable the copilot controls in an emergency and put controls basically anywhere.
 
I like this idea. Could it be consolidated into a single pedal? Push forward a little for the left rudder, more for the left brake, then pull the pedal back for the right rudder, more for the right brake. Perhaps add a single bicycle brake handle to activate both breaks that I could activate by pushing it with my opposite foot.

I see no reason that it would not work as you describe.
 
Jessica,
Agree with a few of the others on the post that a 9A would be a great platform. The controls are so much more forgiving than any other model, except maybe the 10. The 9 has so much rudder surface area and overall authority that with the right modifications you would need little input on a nice flying day. For those gusty x-wind days you could easily get the authority you need without much effort.

Good to know, thank you!

Also would recommend looking at the slider vs. the tip-up and how it will be for managing you entry / exit. The slider has options which may help with the seat position over the tip-up too which is something else to consider.

I would probably prefer a tip up canopy. I've modified things like that before with a long strap to pull it down. But there's also the matter of where it latches.

Thanks for the offer of help. When this idea becomes a pile of real parts and pieces I will be looking for lots of help!
 
Since, like most Ercoupes with Stromburgs, there is only a single throttle power control on the 912- got to thinking when I saw above-

Could not a one-off ish RV-12 mimic the Ercoupe? Reduce crosswinds and aft gear reset to landing crabbed like a no rudder pedal ercoupe.

Link rudders to nose gear directly, not free castoring- like a Rocket link tailwheel.

Brakes, like a Sonex- one motion, shared cylinder to both pistons.

Pitch trim/flaps- is the 12 pitchy at flap extension/retraction?

Is the gain vs Ercoupe by mirroring it with a -12 worth the gains or is a 9A more the target, done similarly?

The Ercoupe is unique in its design to overcome some important challenges with interconnecting the rudder and ailerons. For example, the H tail eliminates the left turning tendency on takeoff. The propeller is angled down and slightly left to minimize other left turning tendencies in flight. I've flown them for 15 years now and I *still* don't understand how the trailing link landing gear allows for landing crabbed. :eek:

I'm not sure we can entirely replicate an Ercoupe with an RV or other airplane, but that nose wheel steering would have me sold!

By the way, if you want to learn more about the Ercoupe, there's a great documentary on YouTube: https://youtu.be/DPxsh6fnSoU

From one of the guys leaving in the C-17 at KOSH'12 Jessica waved at.

That's so cool! Great to meet you on here!
 
Lots of good suggestions so far, but at this point they're all just kinda shots in the dark. The apple guy is asking some of the right questions to get started in defining what is/isn't a possible solution. I didn't see anywhere in the thread the other half of the requirements question, and that is, what are you legally allowed to fly per your license restriction? Does it currently say just an ercoup or are you restricted to anything that links rudder and aileron controls? Are you willing to deal with the FAA to expand your restrictions or would you like a solution that fits inside your current allowables? Gotta define the system level requirements before you start creating the technical solution.

Great question!

I've been poking around since I got my Sport Pilot Certificate on if/how I could get a medical. I plan to pull the trigger soon on getting my Third Class Medical, the Statement of Demonstrated Ability that will come with it, and test for my PPL.

I've also talked with an AME off the record who thinks I could reach the Second class medical, but that's a whole other project.
 
Jessica,

Would it be possible for you to post a list of absolute requirements, followed by strong preferences, followed by "nice-to-haves?"

That might help nudge the discussion into some very productive paths.

For instance, if you really want cargo and passenger capability, an RV-10 might become a "must."

Maybe the list could be further broken down as to:

Flight controls location
Engine controls type
Avionics interface
Cabin/cargo capacity/features/creature comforts

I will try to have a list for you tomorrow!
 
7) I have some movement of my shoulders. I've seen turn indicators on cars activated by large buttons at the shoulder. However, the one thing that has worked is the bar extensions from the handlebars on my bike allow me to steer. It is not fine-tuned control for something like the control stick but might be a more appropriate option for activating flaps or something similar.
Now i'm wondering if this might be the way to do the rudder control. Maybe a harness around the shoulders that could pull on a cable if the shoulder is pulled away from the seat?
 
I had the same thought about shoulder movement this morning while I was flying my RV9. Although I was thinking about stick fore and aft rather than rudder. And adding to that , left and right upper body movement for aileron input . And again my "brain storming" still runs along the line of electrical inputs form those body movements which in turn are driving positioners for the mechanical vans stick yoke there UNDER the seat pans. That might could leave a removable "copilot stick" type option for the Pilot side as well making the option of "conventional" stick input possible.

A electro mechanical device would hinge from the seat back , pull down over the head and attach to the upper body similar to the over the shoulder safety bars on a rollercoaster

Again my brain storming ideas need the input of Jessica and what her preferences are . I guess I was just thinking while on auto pilot at 6500 ft over north east GA while I should have been looking for traffic. But the traffic showing up on ADSB was almost nil and the visibility was 10 miles. Great morning for flying.
 
Let's keep a few practical issues in mind.

(1) Jessica is unlikely to build the airplane, so she will not have a Repairman's certificate, thus an A&P will be responsible for maintenance and condition inspections. Very few A&P's are going to be happy about signing for primary control systems they may not understand.

(2) The mission includes flying other persons with limb issues, including children and their parents. Insurance coverage in the 500K to 1M range is highly desirable. Given low hours and a new Private ticket, Jessica will have enough trouble securing affordable coverage for an RV-10. Significant systems changes will not help when the underwriters are looking closely at risk.

(3) I'm sure Jessica's husband would like to fly, and may choose to obtain a license. There will also be instructors, and mechanics who may test fly, and possible ferry pilots. And all airplanes get sold eventually. Control mods to accommodate Jessica's needs should not compromise the standard controls on the other side of the cockpit, and they should be reversible without significant expense or effort.

We've seen some really cool ideas. However, I'm suggesting the key to success will be found in simple, practical plans, not Elon Musk's neural implant. What is the least complicated approach, requiring the least modification? Is it affordable, and easy to inspect and maintain? Does it leave the RV-10, a proven design, as intact as possible?

Just think about it, while we wait to hear more from Jessica, after she gets a ride in a -10.
 
Mission Requirments

Jessica,

Would it be possible for you to post a list of absolute requirements, followed by strong preferences, followed by "nice-to-haves?"

That might help nudge the discussion into some very productive paths.

For instance, if you really want cargo and passenger capability, an RV-10 might become a "must."

Maybe the list could be further broken down as to:

Flight controls location
Engine controls type
Avionics interface
Cabin/cargo capacity/features/creature comforts

Here's what I've broken it down to:
Primary Mission Outline (aviation specific)
Primary Modifications (specific for me)
Nice to Have's

Because I'm still looking for ideas on control methods, I don't want to limit more ideas ("you don't know what you don't know"). I'm also not worried about the Avionics interface since I can use just about anything out there and reach shouldn't be a problem.

So here's what I'm thinking:

Primary Mission
  • Give kids with disabilities an unforgettable experience to demonstrate that they are not limited by their disability.
  • Support the advocacy of Rightfooted Foundation International (take influencers/politicians/VIPs for a flight for promotions for RFI or to educate on disability issues)
  • Be able to traverse the United States in a reasonable manner: Cruise Speed >130 kts, Payload min 380 lbs, IFR capable, supplemental Oxygen, range >500 miles
  • Fixed tricycle gear
  • External & internal camera mounting points
  • Be capable of meeting the requirements for Canada & Mexico

Primary Modiciations
  • Modify the controls so that the plane can be flown with only feet from the PIC seat.
  • Safe platform for me to fly in most circumstances without a safety pilot (I'm ok with having a second pilot fly with me when doing challenging flights)
  • A ferry pilot must be able to fly the plane when necessary (probably from the right seat)
  • "Minimum workload necessary" philosophy (probably means fixed pitch prop, automatic mixture, spring loaded interconnected rudder, electronic throttle)
  • Adequate knee room on the right side, including hip and upper leg clearance, to manipulate panel instruments
  • Auto pilot
  • Good VFR visibility out the front window
  • High PIC seat
  • Clearance behind panel to make approximately 3/5ths of it 3-6 inches recessed

Nice to Haves
  • Performance +160 kts cruise, 1000 mile range, payload >500 lbs
  • Air conditioning
  • 4 seats
  • Extended range fuel tank options
  • Husband’s request: relatively quiet cabin
  • Additional safety features (TBD, e.g. ballistic parachute)
  • A way to disengage copilot controls
  • Electronic PIC seat controls (forward/backward)
 
The RV 10 will fit most if not all of your needs, as you have them listed.

Various systems will need to be developed, but the basic airframe is what I am referring to.
 
Hi Jessica,

I'm trying to think outside the box a little. How about a rudder bar with brakes on top of a short control stick. 'rotate' for rudder, tilt for aileron, push / pull for elevator.

Maybe the brakes are combined with the rudder bar, the more rudder you apply the more left/right brakes for a castor nose wheel.

My range of motion twisting my feet is more limited than hands. So, I'm hesitant to try a primary control that involves twisting. However, having an incremental knob for something like flaps might be worth while.

A little off your original question but a couple of other ideas:

1) A GTN750 radio and GMC 35C audio panel have a large number of voice commands that will reduce the need for touching small buttons
2) A power system like the Vertical Power series can be programmed to set the electrics (flaps, fuel pumps, lights etc.) according to the phase of flight.

I like the idea of radio controls. I REALLY like the Vertical Power idea!
 
Moving fwd, I think it would be helpful if Jessica could describe the physical abilities and attributes that she has that are outside of what most of us would imagine.

I.E., I would guess that her leg strength (both pushing, pulling, and lateral force) is above that of the average female of her size?
I would also guess that she has a dominant foot just like people have dominant hands? This may not be a design consideration, but if it was, it would be good to know...

Getting some specific numbers is priority. I just got off the phone with Guy Gratton and we have a plan on how to get them.

You posted a lot of other great insights. Thank you! I'm right footed, but my dominance with my foot also lends to using my right foot to make adjustments on the panel, etc. So my left (non-dominant) foot might be better suited to controlling pitch and roll. It will take some experimenting to see for sure.

If we assumed that Jessica would not build a new RV-10 herself, that would leave her having someone build it for her.
The possibly) down side of that would mean it could not be certified as experimental amateur built.
It could however be certified as experimental exhibition, which considering her intended mission, I think it fits with very well.

If volunteers help me as a team and I built portions of the airplane under 'edcuational purposes', how would that affect the experimental designation? I'd like to avoid the paperwork to travel cross country with the experimental exhibition category, but this is all still new to me. Thanks!
 
Now i'm wondering if this might be the way to do the rudder control. Maybe a harness around the shoulders that could pull on a cable if the shoulder is pulled away from the seat?

I would worry about trying to get out of a spin when my torso is being pushed in the direction of the spin.
 
I had the same thought about shoulder movement this morning while I was flying my RV9. Although I was thinking about stick fore and aft rather than rudder. And adding to that , left and right upper body movement for aileron input . And again my "brain storming" still runs along the line of electrical inputs form those body movements which in turn are driving positioners for the mechanical vans stick yoke there UNDER the seat pans. That might could leave a removable "copilot stick" type option for the Pilot side as well making the option of "conventional" stick input possible.

A electro mechanical device would hinge from the seat back , pull down over the head and attach to the upper body similar to the over the shoulder safety bars on a rollercoaster

Again my brain storming ideas need the input of Jessica and what her preferences are . I guess I was just thinking while on auto pilot at 6500 ft over north east GA while I should have been looking for traffic. But the traffic showing up on ADSB was almost nil and the visibility was 10 miles. Great morning for flying.

How does the auto pilot interact with the controls? I assume that the controls move when the auto pilot adjusts something. I would worry about deactivating the autopilot accidentally just sitting in my seat while cruising cross country.

Please keep the ideas coming! Nothing is set yet and all ideas are on the table. And you never know what might inspire something else!
 
Jessica,

I am speculating that your foot may have the same dexterity and precision that I have with my hand; following the logic where we see increases in hearing sensitivity in blind people. I am guessing that you have learned to do things with your feet/toes that I simply couldn't imagine.

If this is the case, I would be considering moving the main contol stick forward into the footwell and develop a type of stirrup on top of the control stick, where you could easily control two axis with one foot, the way that we control it with one hand. You could then move toward developing a rudder bar, as Dan explained, to use with your other foot to make crosswind landings possible. I would think that a lever system could be created that would allow you to grab a throttle bar with your teeth and use neck movement to adjust throttle. To me, that would cover the most intense segment of flight for one with limited appendages - the landing.

For things like flaps, boost pump, etc. I would be looking at a secondary switch panel in the footwell. Again assuming you have the dexterity to operate switches by feel with your toes the way I do with my fingers.

Clearly these ideas will require helpers to implement, but you will not find a better group of people willing to help a fellow aviator and am sure several will volunteer their time and skill.

I sure hope you can find a way to fly our RVs. I admire your dedication.

Larry
 
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Let's keep a few practical issues in mind.

(1) Jessica is unlikely to build the airplane, so she will not have a Repairman's certificate, thus an A&P will be responsible for maintenance and condition inspections. Very few A&P's are going to be happy about signing for primary control systems they may not understand.

(2) The mission includes flying other persons with limb issues, including children and their parents. Insurance coverage in the 500K to 1M range is highly desirable. Given low hours and a new Private ticket, Jessica will have enough trouble securing affordable coverage for an RV-10. Significant systems changes will not help when the underwriters are looking closely at risk.

(3) I'm sure Jessica's husband would like to fly, and may choose to obtain a license. There will also be instructors, and mechanics who may test fly, and possible ferry pilots. And all airplanes get sold eventually. Control mods to accommodate Jessica's needs should not compromise the standard controls on the other side of the cockpit, and they should be reversible without significant expense or effort.

We've seen some really cool ideas. However, I'm suggesting the key to success will be found in simple, practical plans, not Elon Musk's neural implant. What is the least complicated approach, requiring the least modification? Is it affordable, and easy to inspect and maintain? Does it leave the RV-10, a proven design, as intact as possible?

Just think about it, while we wait to hear more from Jessica, after she gets a ride in a -10.

Thank you, Dan. These are great points!

1) How do the various privileges you get when building your airplane translate when it's built by a team? I have a number of volunteers here in Tucson who are willing to help with the build, and some of them are A&Ps.

2) Really good point. And I think this ties in with what you said about the simple design. The easier it is for everyone else to understand, the more likely they are to give it genuine thought. I've had an aviation insurance company (who will not be named) not return a quote or my calls after they found out the policy was for me and my Ercoupe. It's one of those opportunities to turn the situation around and do some educating about disabilities, but that's a whole other issue.

3) Based on my call with Guy today, I think having a copilot who can help me go through a full in-flight control test is mandatory. No matter how much testing we do, there's going to be something unexpected come up (hopefully just something small) so I'll need someone beside me to help overcome that. There will also be some ferry pilots in the mix too, from time to time.

The primary mission is to change perspectives. On one hand (or foot), resale value shouldn't be ignored. On the other, if that's the cost of helping people understand, then hopefully the mission is important enough to pay it. I think the best possible outcome of this build would be to inspire a universal design for controls. Something that will help everybody fly more simply and safer. And maybe the airplane will live on in a second life as a test airplane at a University for further improvement. Or one of the kids I fly goes on to become a pilot and takes possession of it.

I appreciate the practicality you're bringing to the discussion! Hopefully soon we can start making some of these ideas real with some of the prototyping. Thanks!
 
Clearly these ideas will require helpers to implement, but you will not find a better group of people willing to help a fellow aviator and am sure several will volunteer their time and skill.

I sure hope you can find a way to fly our RVs. I admire your dedication.

Larry

Thanks Larry! Your idea of moving the stick forward in the footwell is right in line with what we're going to try first. Many ideas are still in the works!

And the support in this forum has been amazing. Thank you all!
 
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