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I bet my bucking bar cost more than yours. Know what preflight means.

jcarne

Well Known Member
Patron
Hello everyone, as some of you may know I had a little incident while getting very close to done on my project that has delayed it a few months. Some time has passed and I'm ready to tell the story in hopes that no one else makes the same mistake.

So there I was 6 days away from final inspection and I was doing my third engine start to test a new idle setting. I had also just finished setting the last 8 rivets of the entire project while finishing the spinner installation. I have been a pilot since 2005 and have always prided myself on doing a thorough preflight and following checklists. However I made a mistake on when a preflight should be done. I was not planning on flying the plane after this engine start so I did not do a preflight. That mistake ended up costing a lot of money.

Turns out I had left my bucking bar laying on top of my air filter. After starting the engine you can imagine that it found its way into the spinning propeller. I saw something launch into the air (thinking it was a piece of my newly installed spinner) and it landed on my left wing. I shut her down to figure out what was going on. As the prop was coming to a stop I could see a light metallic spot on the prop where black paint should be. It was at this point I knew it was bad.

I got out and found a bucking bar laying behind my wing on the ground. After saying every bad word I could think of and probably inventing some new ones I pushed it back in the hangar and left to go home as I knew nothing good would come of me staying there.

I later went back and decided I needed to take some pictures and see if insurance would cover this. I also looked up the prop strike service bulletin from Lycoming only to confirm my worst fears. Here are some pics of the damage.

20200922_191644 by Jereme Carne, on Flickr

As you can see it punctured the left top outboard wing skin and left a big question mark on what it did to the spar. I decided to drill some rivets out (knowing the skin would have to be replaced) and remove some of the skin to get access to the spar. Here is a picture of what it did to the spar. There was a slight bend in it but not much at all. Van's support looked at it as well as engineering and it was all good to go, no worries at all. Thank goodness, that was a lucky break.

20200923_171353 by Jereme Carne, on Flickr

Here is the damage on the prop. I thought for sure that blade was going to have to be replaced but in the end it could be blended and repainted. Since I didn't lose any RPM (in fact it was still building up to 1000) the prop didn't need overhauled either. The first shop I talked to wanted to do an overhaul and replace the blade but wasn't really working with me on how to get it to them so I took my business else where. I happened to find a YouTube video touring the facilities at Texas Aircraft Propellers and Accessories and knew this is where I wanted it to go. They are a Hartzell recommended service center as well which was nice. They shipped me a box at no charge other than shipping. Great service, HIGHLY recommend them.

20200922_191602 by Jereme Carne, on Flickr

The prop was fixed as mentioned and they didn't even have to take the hub apart which I'm excited about; means I shouldn't have to replace any of my spinner bulkheads. :)

Now for the part I knew was going to be pricey, the engine... According to Lycoming if the prop needs repaired it needs a teardown inspection. I knew this was going to be a completely unnecessary step but rules will be rules. I believe Lycoming even has an AD on prop strikes so the DAR could have refused me certification. I contacted our trusty guys up at Aerosport Power and they made arrangements for pickup. They have been great to work with so far. Here she is all ready to go. It's also worth mentioning that I contacted Lycoming directly and they recommended a teardown inspection.

20201001_220319 by Jereme Carne, on Flickr

The inspection report came back and as I suspected nothing was found. However, Lycoming specifies some things be mandatory replacement like roller lifters (at about 3k worth for anyone interested), bearings, magnetos, and a few other things.

The engine is off to paint and assembly and eventually to test running and I should have it back sometime in early to mid December.

Fixes are under way, wing skin has been replaced and aileron and flap rerigged. Just waiting to put the engine back on at this point.

20201011_180839 by Jereme Carne, on Flickr

So why do I bring this up? What is the takeaway? Well there are a few of them.

1. I mistakenly thought that a preflight wasn't needed since I wasn't flying. In hindsight anytime you turn a mag on you are a pilot and no longer a builder. I will always do a full preflight anytime a mag goes hot.

2. I am never going to set anything on top of my engine again.

3. Get you some builders insurance. Luckily I have had builders insurance for a few years now and boy I'm glad I did because this was many thousands of dollars to remedy. The insurance adjuster even mentioned to me that I am by no means the first person that has ever done this. Highly recommend anyone without builders insurance get some because it REALLY saved my bacon. I was a in a pretty dark place until I found out it was covered. (thought I was going to have to sell the project and cut losses)

4. This could have been much worse if it hit the canopy, fuel tank, or someone including myself. 2 lbs of pure tungsten hitting oneself would not have been fun.

Anyways, safe building out there everyone and I hope this helps someone avoid the same mistake! P.S. Sorry for contributing to raising our rates... I'm sure I'll make it up with my increased premiums. haha
 
Holy cow. That would be the definition of a motivation sucking event.

Thanks for sharing that man. Glad you were able to rally and come back strong
 
What about the tungsten bucking bar, was it damaged? (just kidding now that you have recovered) .
Thanks for sharing as this could happen to anyone. I had a similar situation as I pulled the RV out of the hangar to just try to check XM connectivity. Had no plans to do anything else, then after finishing decided to go to the fuel pump. Opened the canopy and hollered clear prop. , and another pilot came out waiving. I had forgot the tow bar was still attached. He made my day there, I could not believe I had just done that. Lesson here , don't get into plane with tow bar attached.
 
where do you get builder insurance

where did you get builder insurance? Sorry to here about your mishap. I have following your build. I am a little behind you, but you are fast!!:):eek:
 
Please considering modifying your pre-flight inspection policy to include a full walk-around inspection any time you may be motoring the prop. Sometimes "stuff" in on or near an engine or prop and bad things happen as soon as the prop spins. I once saw an expensive prop on a PT6 being held stationary by a work stand during a compressor wash (no fuel introduced, no ignition, just motoring on the starter).
 
Thanks for the replies guys. Just looking to save someone else from making the same mistake. This will save a towbar situation too, very very common.

What about the tungsten bucking bar, was it damaged? (just kidding now that you have recovered) .
Thanks for sharing as this could happen to anyone. I had a similar situation as I pulled the RV out of the hangar to just try to check XM connectivity. Had no plans to do anything else, then after finishing decided to go to the fuel pump. Opened the canopy and hollered clear prop. , and another pilot came out waiving. I had forgot the tow bar was still attached. He made my day there, I could not believe I had just done that. Lesson here , don't get into plane with tow bar attached.

Haha no worries. The bar had a nick on two of the corners. I seriously debated throwing that dang thing in the trash but it wasn't its fault and it will surely provide memories of the event. A little time on the scotchbrite wheel and it looked new.

where did you get builder insurance? Sorry to here about your mishap. I have following your build. I am a little behind you, but you are fast!!:):eek:

Thanks for following! Get a hold of Leah at Gallagher and she will hook you up with some quotes. She posts here from time to time.

Please considering modifying your pre-flight inspection policy to include a full walk-around inspection any time you may be motoring the prop. Sometimes "stuff" in on or near an engine or prop and bad things happen as soon as the prop spins. I once saw an expensive prop on a PT6 being held stationary by a work stand during a compressor wash (no fuel introduced, no ignition, just motoring on the starter).

I hear ya. When I do a preflight I always finish with a walk around to look for the "big things". In this case I just didn't do one period.
 
I have enjoyed reading your post as you build. This post hurt a bit but it’s a great reminder for me to slow down and double check everything. Thank you for sharing.
 
I do have a $1000 flap though

Certainly don't envy the outcome, but thanks for sharing the experience in detail openly and honestly. That's one expensive bucking bar.

While I still have a lot longer to go in my build, and therefore many more chances to stuff-up, the left flap for my -9 cost me in excess of $1000, while the right flap was closer to $100. The reason for the difference was the small matter of temporarily needing extra space and deciding that the roof racks of my wife's car were just the ticket. Suffice to say this particular part of the aircraft had it's first (rather brief) flight about half a k from home, and the dressing down from my wife was harder to bear than the $600 shipping for new parts.

This did make me think about something I used to do way back when I was a volunteer firefighter. I would never, ever move the truck at night, unless I had done a full walk around of it. I didn't even trust my crew saying that everything was OK - if I was the driver I checked myself. Too much risk of injury or damage, for which I was responsible.
 
Please considering modifying your pre-flight inspection policy to include a full walk-around inspection any time you may be motoring the prop. Sometimes "stuff" in on or near an engine or prop and bad things happen as soon as the prop spins. I once saw an expensive prop on a PT6 being held stationary by a work stand during a compressor wash (no fuel introduced, no ignition, just motoring on the starter).

If the mechanics placed the prop there to prevent it from spinning, then that’s fine. (Hitting the workbench isn’t good for the prop or the workbench) I’ve seen a mechanic hold a prop on a PT-6 and fully start the motor! Ignition, fuel, stabilized at idle. No problems at all. It’s a free turbine. It only takes a few pounds to hold it at idle. Let it start spinning, and you have to get out of the way!
 
Polish the bucking bar to a mirror finish, lacquer it, mount it on a nice bit of mahogany wood with a plaque added saying " Pre-Flight trophy":)
 
Many years ago, When I first started working for brand C, they had an employee reward program called the "Leading Edge."

Worked pretty much like you'd imagine- go above and beyond at work and you got a jacket, camp chair, maybe a pretty nice watch, something like that, all with the leading edge logo.

The guys in Experimental Flight (my shop) had made up their own award. If you left a wrench in a wing, or otherwise fubar'd something, The evidence got mounted on a nice walnut plaque labeled "Trailing Edge Award" with your name and date.

Came with magnets suitable for sticking to a tool box, which you were of course, required to do.
 
Polish the bucking bar to a mirror finish, lacquer it, mount it on a nice bit of mahogany wood with a plaque added saying " Pre-Flight trophy":)

Many years ago, When I first started working for brand C, they had an employee reward program called the "Leading Edge."

Worked pretty much like you'd imagine- go above and beyond at work and you got a jacket, camp chair, maybe a pretty nice watch, something like that, all with the leading edge logo.

The guys in Experimental Flight (my shop) had made up their own award. If you left a wrench in a wing, or otherwise fubar'd something, The evidence got mounted on a nice walnut plaque labeled "Trailing Edge Award" with your name and date.

Came with magnets suitable for sticking to a tool box, which you were of course, required to do.

Haha now those are some great ideas.
 
Gosh Jereme. Now we all knew that you LOVED riveting, but thats taking things alittle extreme! That 2 lb tungsten missle could have done ALOT of other damage---like hit someone. So yes, you were being watched over. Great lessone for all of us.

Tom
 
Award

Many years ago, When I first started working for brand C, they had an employee reward program called the "Leading Edge."

Worked pretty much like you'd imagine- go above and beyond at work and you got a jacket, camp chair, maybe a pretty nice watch, something like that, all with the leading edge logo.

The guys in Experimental Flight (my shop) had made up their own award. If you left a wrench in a wing, or otherwise fubar'd something, The evidence got mounted on a nice walnut plaque labeled "Trailing Edge Award" with your name and date.

Came with magnets suitable for sticking to a tool box, which you were of course, required to do.

Our shop had a similar award. If you won it, you had to display it till someone else won it. :eek:
 
Gosh Jereme. Now we all knew that you LOVED riveting, but thats taking things alittle extreme! That 2 lb tungsten missle could have done ALOT of other damage---like hit someone. So yes, you were being watched over. Great lessone for all of us.

Tom

Haha someone else on the field mentioned something similar about riveting again.

I can in fact confirm that riveting a top skin is a lot harder when you don't have the access from below anymore!
 
What about the tungsten bucking bar, was it damaged? (just kidding now that you have recovered) .
Thanks for sharing as this could happen to anyone. I had a similar situation as I pulled the RV out of the hangar to just try to check XM connectivity. Had no plans to do anything else, then after finishing decided to go to the fuel pump. Opened the canopy and hollered clear prop. , and another pilot came out waiving. I had forgot the tow bar was still attached. He made my day there, I could not believe I had just done that. Lesson here , don't get into plane with tow bar attached.

My rule is: If your hand is not on the tow bar, the tow bar gets removed.
 
towbar mirror

I know someone who keeps a hand held mirror in the cockpit for checking the towbar is off before starting up. He previously had a towbar incident, luckily it came off before he was in the air.
 
Haha someone else on the field mentioned something similar about riveting again.

I can in fact confirm that riveting a top skin is a lot harder when you don't have the access from below anymore!

Uh...ya, I second that statement...:)

...but the MACHINE has built, broke, and repaired his plane faster than most decide which rivet to use and where...:D
 
Yup aloes do a preflight. We lost an ah-64, because the pilot and gunner (bolth killed) lit the fires withought doing one. Canopie lock bar was left on the top of the doghouse, by the crew chief. Big red thing 6 ft long. Should’ve bin hard to miss when the pilot got in. As it was just a couple ft from his eyes when entering.
And as the QC of note on the ship’s critical components (main and tail rotors) I was grilled by a panel of 6 for 3 days. Till bar was found and the crew chief fessed up. Bar went through the tail rotor, taking out a blade. Sad thing all round. Glad you weren’t injured.
 
My rule is: If your hand is not on the tow bar, the tow bar gets removed.

very good rule. Hangar neighbor bought a new engine when his son got distracted during preflight. Hopped in, cranked up, took off. Noticed the problem when he landed and the engine stopped, with prop vertical. He was missing about 2-3 inches. Never did find the tow bar.

Anytime I get interrupted during preflight, I restart from the beginning. Period.
 
Although my bucking bar story didn’t cost me anything (yet), it could have, or might. ....
I was under my left wing of my RV4 (I’m not the builder), cleaning off some dirt from the bottom of my flaps. I looked up at the bottom of the wing in that area and noticed several tiny dents. Funny thing was - these dents were pointed out, not in. I removed the only inspection panel on the bottom of the RV4, and started feeling around inside the wing. I have long arms, so I was able to reach inboard far enough to get to the bay where the dents were. This is what I found inside the wing:

432C5AC6-60DE-49D2-B0D5-A9ABC72AA48C.jpeg

The bucking bar was mostly wrapped in duct tape. I’m sure it has been inside the wing since it was certified, and I’m also sure those dents weren’t there when I bought it. Over the 14 months that I’ve owned it, I’ve done a fair amount of positive G acro, but none negative. Hence in the dents in the bottom skin, but none in the top. I weighed the offending bar and it weighed 2 lbs. My new empty weight is now 979#.
 
Yup aloes do a preflight. We lost an ah-64, because the pilot and gunner (bolth killed) lit the fires withought doing one. Canopie lock bar was left on the top of the doghouse, by the crew chief. Big red thing 6 ft long. Should’ve bin hard to miss when the pilot got in. As it was just a couple ft from his eyes when entering.
And as the QC of note on the ship’s critical components (main and tail rotors) I was grilled by a panel of 6 for 3 days. Till bar was found and the crew chief fessed up. Bar went through the tail rotor, taking out a blade. Sad thing all round. Glad you weren’t injured.

This goes to show that it certainly could have been worse. Thanks for sharing.

very good rule. Hangar neighbor bought a new engine when his son got distracted during preflight. Hopped in, cranked up, took off. Noticed the problem when he landed and the engine stopped, with prop vertical. He was missing about 2-3 inches. Never did find the tow bar.

Anytime I get interrupted during preflight, I restart from the beginning. Period.

Great idea. A buddy of mine forgot to put a fill cover back on his engine awhile back after being interrupted during a preflight. Turned out okay but with a bit of oil all over the plane including the windscreen.

Although my bucking bar story didn’t cost me anything (yet), it could have, or might. ....
I was under my left wing of my RV4 (I’m not the builder), cleaning off some dirt from the bottom of my flaps. I looked up at the bottom of the wing in that area and noticed several tiny dents. Funny thing was - these dents were pointed out, not in. I removed the only inspection panel on the bottom of the RV4, and started feeling around inside the wing. I have long arms, so I was able to reach inboard far enough to get to the bay where the dents were. This is what I found inside the wing:

View attachment 4340

The bucking bar was mostly wrapped in duct tape. I’m sure it has been inside the wing since it was certified, and I’m also sure those dents weren’t there when I bought it. Over the 14 months that I’ve owned it, I’ve done a fair amount of positive G acro, but none negative. Hence in the dents in the bottom skin, but none in the top. I weighed the offending bar and it weighed 2 lbs. My new empty weight is now 979#.

Hoping you dodged a bullet with the wing spar Scott. Thanks for sharing!
 
Jereme,
Yep, the wing spars (fore and aft). That’s pretty much why I bought a boroscope. Nothing obvious so far, but I’m learning the scope. Fortunately everything internal was primed so a ding might be more obvious. I’m keeping my eye on it. I have a 6’ lead on my scope,and it has two camera angles on the tip, so I can see a lot.
 
It happens . . .

I worked as a mechanic for years during college and many projects since and always took pride that a tool was never lost or left in a vehicle.

Some time following assembly of my 7 at the airport and first flight, I organized my tools and discovered a Craftsman 9/16" combination wrench was missing. After months of looking at the hangar, back home in the garage and basement shop, a new one was purchased.

During the first condition inspection everything was rechecked just like first flight. Much to my (up to now) private embarrassment I found that wrench in the wing to fuse cavity where it was used to tighten the aft wing spar connection. No negative Gs, but a hammerhead was performed during Phase I, and no noticeable damage. I considered myself quite lucky.

It appears you have recovered well, and not alone. There is always a first time.
 
I worked as a mechanic for years during college and many projects since and always took pride that a tool was never lost or left in a vehicle.

Some time following assembly of my 7 at the airport and first flight, I organized my tools and discovered a Craftsman 9/16" combination wrench was missing. After months of looking at the hangar, back home in the garage and basement shop, a new one was purchased.

During the first condition inspection everything was rechecked just like first flight. Much to my (up to now) private embarrassment I found that wrench in the wing to fuse cavity where it was used to tighten the aft wing spar connection. No negative Gs, but a hammerhead was performed during Phase I, and no noticeable damage. I considered myself quite lucky.

It appears you have recovered well, and not alone. There is always a first time.

Thanks for sharing Bill. I was surprised to hear the insurance man say that I'm not the first one that has done this. Live and learn.
 
is it common that builders insurance covers damage by an engine start? i assumed you need taxi ins. at least?
 
is it common that builders insurance covers damage by an engine start? i assumed you need taxi ins. at least?

From what I can tell on my policy it covers an aircraft that is still under construction and the aircraft not in motion and "does not get away from you" IE lose control. I was told by my broker that it even covers putting fuel in the tanks and starting the engine. In short, I think it covers aircraft under construction that's not moving. If you start taxiing I don't think you are covered anymore.
 
OK, I’m going to ask. Flame suit is on... Did the engine really need to be torn down from that prop strike? Seems the hit to the prop was so close to the hub that damage to the engine is extremely unlikely. What could possibly be hurt in the engine from that hit? I guess if the insurance pays for it, it’s worth while.
 
OK, I’m going to ask. Flame suit is on... Did the engine really need to be torn down from that prop strike? Seems the hit to the prop was so close to the hub that damage to the engine is extremely unlikely. What could possibly be hurt in the engine from that hit? I guess if the insurance pays for it, it’s worth while.

I agree that a strike of this nature was not likely to turn up any damage but the word for a prop strike inspection came straight from the horses mouth at Lycoming. Their SB is very definitive; if there is propeller damage that has to be repaired it must go through the tear down. The only thing I could think that would likely have been damaged would be the "Jesus pin" and gear bolt. If one of those fails you are guaranteed to have a glider on your hands.
 
I agree that a strike of this nature was not likely to turn up any damage but the word for a prop strike inspection came straight from the horses mouth at Lycoming. Their SB is very definitive; if there is propeller damage that has to be repaired it must go through the tear down. The only thing I could think that would likely have been damaged would be the "Jesus pin" and gear bolt. If one of those fails you are guaranteed to have a glider on your hands.

And, a small number of critical parts get replaced automatically during a prop-strike teardown (aka: bulk strip)
 
Here's one that happened many, many years ago in our flying club, long before I was a member, so this is just word of mouth.

After a flight, the pilot smelled "something funny" around the engine. Found a screwdriver that had been left on top of the engine, and the plastic handle had melted all over the cylinder.

I *always* use a flashlight to look inside the cowling inlets at the engine as much as I can see when preflighting based on this story. Never just peering inside with my hand shielding my eyes to try and make things out. And there's a reason my toolboxes are very carefully arranged, rather than just drawers with similar tools tossed in at random into their respective drawers...I can see at an instant if a tool hasn't been returned (ultimate would be to shadowbox them with foam or something, but I have way too many tools to do that :) ).
 
Happens all the time in the backwards plane community! One time after an oil change we left a cup with screws on the wing. After turning on the engine it got sucked into the prop and completely destroyed the prop. Made the worst sound ever. Now we do a complete pre flight inspection every time we are going to turn on the engine.
 
Being a experimental, do you really have to tear down the engine?

Depends how your DAR interprets the rule. There is an AD on Lycoming engines for prop strikes. If he says he won't sign the papers until it's complied with then I would say yes. ADs for experimentals are certainly a big grey area but not always.
 
Happens all the time in the backwards plane community! One time after an oil change we left a cup with screws on the wing. After turning on the engine it got sucked into the prop and completely destroyed the prop. Made the worst sound ever. Now we do a complete pre flight inspection every time we are going to turn on the engine.

I can imagine what that prop looked like... To add to that, I have always wondered how many cups of coffee have ended up in a prop on pushers. :eek:
 
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