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Join the 200Kt club

I'm gonna put this one up just because I like the numbers. Groundspeed is nice (221 knots) but check the TAS vs fuel flow, 192 at 9.8. Settings are simple; WOT, adjust RPM for an indicated 65%, and lean to peak at 23 degrees BTDC.

Pressure recovery for the combustion air intake is pretty good. 21.4 Hg is measured at the usual #3 intake port. Static pressure for this altitude and temperature is 20.98, so delivered MP increase due to ram is 0.4" Hg after all intake tract losses, here including a filter which hasn't been cleaned since last January.

How much intake tract loss? Total pressure at this PA, temperature, and velocity is 22.3 Hg, but you can't recover all of it for several reasons. In the case of an engine intake (and just like cooling air), the noteworthy factor is that the "pitot" is not a closed end system. At 2500 RPM, if we assume engine VE is 90%, the calculated total pressure inside the airbox, before the filter, would be 21.9 rather than 22.3, so the overall intake tract loss for the 390, with filter and FM200, appears to be about 0.5" Hg.

Please excuse the crappy photo. The sun was at an entirely wrong angle.

2500_RPM_Cruise_12122018.jpg
 
Whhhhhatttt.......

Only 23 degrees BTDC?

You don't need the fancy ignition system gear for good fuel economy? :rolleyes:

Keep in mind that this is "Peak" EGT and the flame front is still moving pretty rapidly. Go LOP and the advance requirements change quickly.

Also keep in mind this is an angle valve with a better combustion chamber AND higher compression than standard, to boot. 23 degrees is a relatively steep advance.

If you are to add the 5 degrees to compensate for the less efficient parallel valve combustion chamber, a few more to make up for the higher compression, and then the 4 that I add when going 30 LOP, sudenly you have your advance in the low 30's.

If you want to throw in another wrinkle, consider that Dan is running a dual system. If you want parity with all those guys running an electronic on one side and a mag on the other, you have to add ANOTHER 5 or so degrees. Now you are up in the high 30's, knocking on the door of 40. Yet this same engine at a sea level TO power will need ~ 22 degrees. Do you know of a "simple" ignition that offers that range of adjustment in normal operation?

So as it turns out "fancy ignition gear" IS a required tool for good economy.

Dont mean to turn this into another ignition thread, but the "cheap shot" needed a response from someone who has done the flight testing and knows better.
 
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You're both right, and it wasn't a cheap shot. Technically speaking, it's not a fancy ignition system (a Ford module with a sub-$200 timing controller), and it is 23 degree fixed timing when running on this ignition map. I have two, switchable in flight, but a fella can probably do it with mags if given the other airframe changes.

I can run this angle valve for more economy, and if chasing economy alone, I'd be at less RPM, LOP, and out around 27~29 degrees, which is the other ignition map. However, I would also be slower. This is a speed thread. The point is 190 plus KTAS on less than 10 gph. It makes 200 knots GS a near sure thing for the windward leg of most flights, without breaking the bank. I like it.
 
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You're both right, and it wasn't a cheap shot. Technically speaking, it's not a fancy ignition system (a Ford module with a sub-$200 timing controller), and it is 23 degree fixed timing when running on this ignition map. I have two, switchable in flight.

I can run this angle valve for more economy, and if chasing economy alone, I'd be at less RPM, LOP, and out around 27~29 degrees, which is the other ignition map. However, I would also be slower. This is a speed thread. The point is 190 plus KTAS on less than 10 gph. It makes 200 knots GS a near sure thing for the windward leg of most flights, without breaking the bank. I like it.

I believe Scott's intent was to diminish the importance of a "fancy" variable timing system.

In sharp contrast, here is but one post on a flight from a couple years ago which very clearly illustrates the value of variable (and most importantly "correct") timing.

http://www.vansairforce.com/community/showpost.php?p=1099002&postcount=53

For those who dont want to read it, let me summerize: thanks to the correct timing curve I was able to match your speed AND FF in my heavy, loaded to the gills 540 Rocket on a hot day. I saw 191KTAS @10 GPH - could not have done that without direct control of the timing bump needed for LOP ops.

So to return this thread back to the boasting about speed:

Congrats Dan, you have managed to get your slick, highly refined speedster to match my overloaded, coarsely built and significantly overpowered Rocket for speed and economy! ;)
 
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The point is 190 plus KTAS on less than 10 gph.

And that was my point as well.

I'm fully aware that the quoted fuel flow isn't as low as it could be if ultimate range economy is the goal.....
The point was that considering the speed it is still impressive fuel economy without advanced tech like automatic variable timing, etc.
 
Didn't get a picture, but we hit a ground speed of 231kts on my very first flight in my newly purchased 6A on our way home from California. Nice way to start things out.
 
Suppose Van's did come out with a fabric covered Super-Cub-ish plane, with rib stitching. That could give the 200-knot club a whole different meaning...
 
My ground speed exceeds 200k so often I don't even get excited about it! What I truly aim for is 168k TAS sipping 7 GPH or better! If I can find an altitude with a tail wind, all the better.
 
My ground speed exceeds 200k so often I don't even get excited about it! What I truly aim for is 168k TAS sipping 7 GPH or better! If I can find an altitude with a tail wind, all the better.
At what altitude to you get this speed/fuel burn, it is awesome.

I have had one small cross country trip so I was only at 10500 and was getting same speed or a bit better but at 8.2G, of course I had a nice tailwind and did reach the 200K club thru the ground speed
 
My ground speed exceeds 200k so often I don't even get excited about it! What I truly aim for is 168k TAS sipping 7 GPH or better! If I can find an altitude with a tail wind, all the better.

Wow I've never heard of speeds using such low amounts of bang water, what's yr secret?
 
I finally was able to hit the magic 200+ Knot ground speed on the way to the Copperstate Fly In. This is of course only possible with a really strong 44 Knot direct tailwind, but it is in level flight with "Otto" the pilot at the controls. The green circle on the map is my "glide ring", you can see how skewed it is towards the North East. At one point I saw a 48 knot tailwind. It was actually quite smooth all the way out to Buckeye, AZ. I decided to enrichen the mixture a bit and see what the true speed of the airplane could be at altitude.
My usual 6.5 gph speed is around 147-150 Knots (LOP), so with 9 gph it was going only 8-10 knots faster.

screenshot-N5771H-SN03222-15.3.4.4867-20190209-073807-165-en_US-M.png
 
Yesterday was sporty...

Yesterday was a wild ride. This picture was taken at only 3500msl. If I had climbed, I could have seen larger numbers but the trip too short to warrant that. I kind of wish I had turned around and flown a backwards ground track. I have never done that before. On return home the winds made for a non-boring crosswind landing... :)
IMG_3131.jpg
 
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Rejoined the club on the way back from IA yesterday:

32277424867_d99240f365_c.jpg


Rough math shows 278mph, over 20mpg - and I don't have my injectors balanced yet and wasn't really leaned for efficiency.

Not bad for a 4 seat traveling machine that hauls whatever I stuff in it!
 
Gee that's a very high engine RPM? I almost feel sorry for your donk:D

Haha - I had to google that, my Australian is a bit rusty!

I was running fast, just for the purposes of maximizing TAS to see how far into the 200kt club I could get. Max RPM for the IO-540 in the -10 is 2700...
 
WOW! T Short!

Congratulations! For a minute there I thought I was going to need to start the 300MPH club! Fantastic planes and Wonderful Tailwinds. Very Impressive!
 
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Fast and Slow

As most of you know, joining the 200kt club in our machines is a regular occurrence. I was just out playing last week and with these crazy winds we've been having in the TN valley, I recorded my fastest and slowest ground speeds in level flight yet, with not a whole lot of effort.

FAST:

9sgw1x.jpg


SLOW:

2nv9zd0.jpg
 
65 knot tailwind across canada

Flying MI to Vermont over Canada and picked up a nice tailwind. Fastest I have seen in my newly finished RV10.
GS235.jpg
 
Our flight

On Friday afternoon on our last leg from TX to NH, about 90 west of Nashua, we had a nice quartering tail wind at 9500 when we had to deviate left to avoid
building clouds. When we turned back the tailwind aligned perfectly to give us
a 200 knot ground speed. Shortly after when the vsr got to 400 and we started down we got to 207. Nice flight.

https://i405.photobucket.com/albums...3EB/57003EEF-4F1F-4EA6-98AC-90ED4FE479B9.jpeg
 
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Saw 217 kts GS the other day at 9500'. 173 TAS so was operating in the yellow arc mindful of any turbulence. That was at 32Lph, pretty good speed for that FF:)
The highest I've ever driven a plane was 645 kts GS, ahh the good old days, now retired loving the dream:)
 
What I thought was going to be highly improbable to achieve and left to the more-powerful RVs happened this past Saturday. Took advantage of a crisp, cold fall day, grabbed my oxygen, and went searching for my 9A's service ceiling. I didn't quite make it there - an air gap between my canopy skirt and the fuse was making for quite a chilly cockpit, even with heat. 21F made for some frosty hands!

But I made it in the 200kt club! That was one heck of an incredible tailwind I got when I turned to take advantage of it. :eek: Probably would've been even faster if I kept climbing. WOT here at 15k and the climb rate was still at least 400fpm at 90 KIAS when I leveled out. And this is on a typical 3-blade Catto FP, not repitched or anything, and 150 HP engine. Now I'm getting impressed at where the -9 likes to live, going multi-state cross country.

mtCTfMVidQJ43nl7I8JpFkKcPsr6edCMubFJR-KlAvTHtru8bOKQgIgPeqbxHMjVoTyScAxKZNjblJJZezgan-kztjn8RBxBaW1L7V97lgTSdR1HPifgll2mcgTNkfc-yvA3cHpMXNr3VhDWK10yjRbRE2IrA33BY9xNRAi8Ai4y8bT0Nyqj2B0MgboK7CxK3cmyuVc58Vy5oEkN79kQtI_t5p3eoTrKrmGIS1SumWGj2fHMllIPpsgeSAXC5iHatELAgwB2Uj7wHKFwaYuKW4q6lbb52X0VhU51nuyKGZsYirQiJC3qU4QD-5-5qryCRipNbvFhB_e_5pq0NFq9Y1MGcMyuXcVVffX8R6bidAa1eDs_6qiq3-ORQ1Ax5h9paM4SbuTYe1ESBSmtusUs_Oqqzds0JBdn0DDkqZl3dxdORJWNwPQiNhMriMiWaD3eJmvCjCgJtaT5VsYUllht8si9FCWkhhwcRJQlUXMoItvMN9M_yIslYRyInXKz4pQe7kLT8HsVbufzix6ANLPhnaQKD0v7OInY3WwEOBhLK9cl4y3KPJeLW6raGdGvjIsSKIm2t-RqJ24_HWX3Y0gyWDNzUaXfqcA9cPqawLCDycX0tt0j7v1K3NFCgHwr0zQsdd56SCPRkPdKCRU-irL5uwCAK3aOpnMQWq-X4nZ0p_YAA35bn6N-UFg6ynCF1s8o3qUfvqKUryfiUQdyOJyZXbx6YG0wIyYgCTuIJxhdoa5r6_Di=w1069-h802-no
 
Light and fast...

Cruising back from a lunch run over central Texas. Smooth as glass with ~40kts on the tail.

1475.bmp
 
210 kts reported by flightaware

First time to claim 210 knots in the RV8A: on my way home from HSF (north of Reno) to Ely on October 19. Across the state of Nevada, 1.5 hours flight. I observed 207 kt GS on the Advanced Flight EFIS. But flightaware was looking when I wasn't and shows a hit at 210 knots.

I don't upload pics to VAF but the flight track show I was actually in a slight climb at the time of 210 knots. The track ends shortly after due to limited radar coverage in the eastern part of our state.

https://flightaware.com/live/flight/N4032Q/history/20191019/1832Z/tracklog

Zoom zoom baby, bring it!
 
Looks familiar

Coming back from Big Bear this morning:

oFb.jpg

I took my PPL check ride at LGB. I was flying out of Meadowlark (L16) in Huntington Beach, just south of the SLI VOR. Can't believe it's been closed and turned into a shopping center and subdivision for 30 years now.
 
200 kt Club / 300 kt Club

I hate to post this because I was flying on 48% power with the following setting: 2220rpm, 1/2 throttle, climbing at 250fpm, 15,480'. IAS = 153mph, TAS = 197mph, Ground Speed (GPS) = 265kts, or 305mph, wind speed = 110mph.
photo.php
 
I missed the photo op. Had smooth cookin' uppers and hit 200 kts. By the time I got my camera and snapped I was at 194kts GS level at 12.5k elev.

If I had oxygen I could of hit 220kts that day as the uppers were fast and smooth.
 
I was too excited and forgot to take a pic of my EFIS. On December 31 at 9,000? burning 7.2 gph my 9 hit 215 kts. flying from 1A3 to KSFB.
 
I hit 203 kts yesterday at 6,500? in my 9 with an O-360 engine mated to a three blade Catto prop. How cool.
 
What a tail wind!

Thursday 5/7 on the second leg of a relocation from Michigan to Florida, RV7 N50KB joined the club; 215 kts ground speed!
There was a 72 kt tailwind component while cruising on 59% power at 14,500 ft msl.

200kt EFIS.jpg


The 25kt crosswind component caused the 7 deg. crab to the West.
The personal intermediate fix (USR00) was set to take the route around a restricted area.

200kt GTN625.jpg


I had set up a VNV profile to descend to 1100 ft ten miles before the KBKV destination. The GTN computed this to start in 53:40 minutes.

200kt MFD.jpg


247mph and 9.9gph = 24.9 miles per gallon.
PS: Do I need GAMI injectors?
 
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Thursday 4/7 on the second leg of a relocation from Michigan to Florida, RV7 N50KB joined the club; 215 kts ground speed!
There was a 72 kt tailwind component while cruising on 59% power at 14,500 ft msl.


247mph and 9.9gph = 24.9 miles per gallon.
PS: Do I need GAMI injectors?

Wow! Welcome to the club. We've been getting some strong southbound tailwinds here recently. Welcome back to Florida. We'll have to get together at KBKV, since there's no Oshkosh this year. At least, we have cheap fuel. $2.60/gl.
 
Thanks Dan,
I'd like to hear more about your Pilots-N-Paws activity. Maybe do some of it myself if it wouldn't cut into your game. How does it work, etc.
 
200 knots

Just bought an RV9A and on the way back from Yakima WA to Lancaster SC, had this for speed over the top of the 12,500' Class B ceiling at Atlanta GA. Oh well, dont know yet how to get pics to work. It was 244 mph Ground speed.

ovL18YNw8iMWi1gW7
 
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Over NC yesterday there was 50 knots of wind out of the west at 8500 feet. Sadly I was going West! Faced with a smooth ride and big headwind or bumpy ride and 35 knot speed gain. Picked the bumps!
G
 
239 kts GS

Near KOPL - St Landry Parish Airport-Ahart Field

Very nice tailwind at 15.5. 239 kts ground speed in level flight. If my math is correct, that’s 275 mph.

0DACB1F2-7EBC-462D-9A70-52646B7DAD64.jpg
 
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200kt GS today.

31 knots on the tail makes things pretty easy. :) Need a little left rudder...

IMG_2603_HEIC-X3.jpg
 
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