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First Flight Report! (RV-7)

Flyguytki

Flyguytki

Well Known Member
Yes it flew, but I had a few engine issues. Before I post everything that happened, I would really like to consult an A&P who is really good with lycoming/superior engines. If you would be willing to take a phone call from me I would really appreciate.

The good news is, The airplane is still in one piece and from what I can remember it flew great, I had a lot going on so there wasn't much time to "enjoy" it.

Heres a screenshot of the data download to get a glimpse, this happened on climb out.

Flight_zps44bb1f26.jpg


Please if you would have a few minutes and could talk it would really help me out.

thanks

-david
 
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Congratulations!!

David, congratulations on the maiden flight:D

We need a "Grin" photo................
 
David,
Congrats on first flight.
How was the run up??
Mag check
Fuel flow
Did you lean at 8:00 ???

Boomer
 
It looks like you put the matter in your avatar to good use today David. Good job and congratulations.
 
David,

An easy starting point is to check the EGT probe connections for security and then trace the wiring from the starting point to its endpoint for chaffing or a shielding short.

Regards,

Robert
 
I would also like to know if there was obvious roughness or loss of power, or was this strictly something on the gauges. It looks like this was a little over a minute after adding full power. Even so, your rpm seems really low. Is the rpm correct, were you at just over 2000 rpm? Is this a new or newly rebuilt engine?

Bob
 
Brand new engine, the engine was only producing 2080 rpm and by the time I realized that was all it had, ( I brought throttle in VERY slowly) I was already airborne and wasn't positive I had enough runway remaining, so I began a shallow climb out and when I turned crosswind I lost apx 1000 rpm (I thought it quite on me), I had not touched anything prior to this point, as soon as it happened, I turned hard back to the airport and pulled the throttle back, considered landing opposite however I was a good 1200 feet in the air and I never would have made it to the runway I was way to fast and high with the runway directly below. At this point with the throttle pulled back to 1/4 throttle or so and the power felt as if it came back and it was running smoother so I continued downwind, turned a tight base, final, dumped some flaps, engine was at a lower rpm and again running smoother, cleared the fence at about 90 knots and floated forever, but it was a beautiful touchdown :).

When I shutdown I got many questions of "what was this reading". I could not tell you until I downloaded the data, as I keep looking back on it, from the second I thought the engine quit I do not recall looking inside.

Our initial thought ( prior to downloading data, however we did have a gopro looking at one of the screens showing the ems that we could watch at the airport) was that I had stopped making power on the #1 cylinder, because the egt cht starting to climb faster than the other 3 cylinders and then when I had the loss of power it dropped completely off. Also the exhaust is very black, ie very rich, so our reasoning for the cylinder not firing is a plugged injector or blockage somewhere in the cylinder, that would make force more fuel to the other cylinders making then rich, #1 plug looks normal, #234 are VERY black. We pulled the injectors in #1 even swapped then with another cylinder to see if when we did a run in the problem followed to the new cylinder but there was no change. And the max rpm is still 2080.

Please no speculation on what I did wrong, I need to know what's going in with the engine and that's all, I have to give a huge thank you to RVG8TOR as he was flying chase and took care of the tower for me ( no emergency declared but they let us do whatever we needed to get back in the ground) so once again thanks mike.

If you think you might be able to give some insight please give me a call if you would. Two one four 7 3 3 two two six two

-david
 
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Bruce said:
David,
Congrats on first flight.
How was the run up??
Mag check
Fuel flow
Did you lean at 8:00 ???

Boomer
Click to expand...

Runup was fine, very smooth, it ran smooth just wasn't producing full power until I had the drop in rpm, the the proverbial something hit the fan.



For those interested and to see if anyone can gain any insight, here is a link to the flight, and then the high speed taxi run after some troubleshooting. take a look

https://www.savvyanalysis.com/my-flights/2492/a6ab2f8e-8226-4105-a64f-ec73390ce7ea
 
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This is a forum where we all come to discuss and learn and this looks like a perfect opportunity. Glad you made it back on the ground safely!

Appears to be fixed pitch with dual P-Mags from your website. Fuel flow at full throttle run up? Static rpm should be greater than 2,100. Exhaust valve sticking? Some good troubleshooting info here...

http://www.emagair.com/TroubleShoot V03s1.pdf
 
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Well done

Good job , you kept flying the aircraft until it was back on the ground. Turning a bad situation around with a good outcome. I hope you get your engine sorted out soon.
Regards
Arie
 
Wayne Gillispie said:
This is a forum where we all come to discuss and learn and this looks like a perfect opportunity. Fixed pitch or CS? Exhaust valve sticking? Glad you made it back on the ground safely!
Click to expand...

I agree, I know there is alot of knowledge here so hopefully I can get some help.



Catto 3 Blade FP, Superior IO-360 180HP, dual P mags, Horizontal Induction,
 
Did you do a baseline compression test? I'd do one now and also boroscope cylinder #1.

Your max IAS shows 32.9 kts? I think your MP at idle on the ground should be around 10-12".

You may find you have more than one problem.
 
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Good job getting safely back on the ground.

#1 cylinder looks like it goes lean at higher fuel flow, but runs OK at lower fuel flow. Look for some crud in the #1 fuel injection nozzle.
 
He already troubleshot the nozzle..."We pulled the injectors in #1 even swapped then with another cylinder to see if when we did a run in the problem followed to the new cylinder but there was no change. And the max rpm is still 2080."
 
I am pleased to report I think we have solved the issue.

This morning, a group of 4 of us sat around and brainstormed everything that could possibly be the answer, we had the SavvyAnalysis up at the same time and we kept coming back to the same reasoning, Cylinder one had a fuel blockage at the time of the RPM decrease, this answered everything except for the low RPM on take off. Well after searching this site for about an hour, I came to the conclusion that Static RPM is not an exact science with this engine and prop combination. Some have reported static RPM's as low as 2100 all the way to 2400 Rpm. After some more troubleshooting we ran out of things to look for and decided the next thing to do was fly it again.

The take off was similar to yesterdays, 2050 RPM and airspeed was reading about 100kts on climb out. As I climbed through 1000 feet the RPM's steadily increased, increased increased, as I leveled off at 3000 feet, the RPMS were right at 2500, CHT's were reading 1250-1300 and EGTS were right at 410-420 while cruising laps around the airport at 160kts. After relaying all the info to the ground, i got the "Everything sounds normal" so i kept cruising, 48 minutes into the flight i started a slow decent straight into a base final and an OK landing. Needless to say, I am MUCH happier, Mike was even able to catch the "Grin" after I shut down.

I am going to go back out again tomorrow and see if things are the same, we suspect the low Static RPM is due to a brand new engine and some very thick mineral oil.

photo-6_zps0dd47cac.jpg
 
Great Job!

Flyguytki said:
Brand new engine, the engine was only producing 2080 rpm and by the time I realized that was all it had, ( I brought throttle in VERY slowly) I was already airborne and wasn't positive I had enough runway remaining, so I began a shallow climb out and when I turned crosswind I lost apx 1000 rpm (I thought it quite on me), I had not touched anything prior to this point, as soon as it happened, I turned hard back to the airport and pulled the throttle back, considered landing opposite however I was a good 1200 feet in the air and I never would have made it to the runway I was way to fast and high with the runway directly below. At this point with the throttle pulled back to 1/4 throttle or so and the power felt as if it came back and it was running smoother so I continued downwind, turned a tight base, final, dumped some flaps, engine was at a lower rpm and again running smoother, cleared the fence at about 90 knots and floated forever, but it was a beautiful touchdown :).

When I shutdown I got many questions of "what was this reading". I could not tell you until I downloaded the data, as I keep looking back on it, from the second I thought the engine quit I do not recall looking inside.

Our initial thought ( prior to downloading data, however we did have a gopro looking at one of the screens showing the ems that we could watch at the airport) was that I had stopped making power on the #1 cylinder, because the egt cht starting to climb faster than the other 3 cylinders and then when I had the loss of power it dropped completely off. Also the exhaust is very black, ie very rich, so our reasoning for the cylinder not firing is a plugged injector or blockage somewhere in the cylinder, that would make force more fuel to the other cylinders making then rich, #1 plug looks normal, #234 are VERY black. We pulled the injectors in #1 even swapped then with another cylinder to see if when we did a run in the problem followed to the new cylinder but there was no change. And the max rpm is still 2080.

Please no speculation on what I did wrong, I need to know what's going in with the engine and that's all, I have to give a huge thank you to RVG8TOR as he was flying chase and took care of the tower for me ( no emergency declared but they let us do whatever we needed to get back in the ground) so once again thanks mike.

If you think you might be able to give some insight please give me a call if you would. Two one four 7 3 3 two two six two

-david
Click to expand...

I just flew and watched as you handled a very challenging situation like a pro. Congratulations on the first flight and well done.

Glad today's flight was much more normal, nice temps on the engine, I think you plenum will work out nicely.

Seems like only yesterday I was picking up your finish kit while you where still in Afghanistan. Let me know when you want to start some formation work!
 
RVG8tor said:
I just flew and watched as you handled a very challenging situation like a pro. Congratulations on the first flight and well done.

Glad today's flight was much more normal, nice temps on the engine, I think you plenum will work out nicely.

Seems like only yesterday I was picking up your finish kit while you where still in Afghanistan. Let me know when you want to start some formation work!
Click to expand...

We were shooting emails across base in Afghanistan, got home about the same time, projects in about the same place. I'm not even CLOSE to done! I'm so jealous, congrats brother!!!:D
 
RPM Spread

I agree that it looked like there was some kind of short term loss of fuel to #1 that cause the power disturbance. Congrats on successfully working through it!

Generally speaking, 400-450 RPM spread from Static to WOT on a fixed pitch prop is pretty "normal". It is the achilles heal of fixed pitch. I saw the same spread on several different props I ran on my Long-EZ. Ideally you should have top end (8000 ft / WOT) RPM of around 2650-2700, which would give you ~75% power at 8000 ft. That gives you the highest cruise speed and with electronic ignition and FI you can lean to get good fuel economy without having to throttle back. That would also give you around 2250 RPM Static. Your current 2080 RPM will definitely cut into your take off performance when you need it the most for Gross Wt, high density altitude operation. R
From my personally experiences, I wouldn't be comfortable with settling for that.

2500 RPM WOT is "nice" for WOT cruise, but you'll suffer top end speed from it also.

FP is a notable compromise on these "high speed range" aircraft.... so you have to decide how you are most often going to operate the plane and understand the associate limitations. If it were my plane, I'd seriously consider re-pitching or blade length to get some more RPM's...

Just my 2 cents...
 
rv9av8tr said:
I agree that it looked like there was some kind of short term loss of fuel to #1 that cause the power disturbance. Congrats on successfully working through it!

Generally speaking, 400-450 RPM spread from Static to WOT on a fixed pitch prop is pretty "normal". It is the achilles heal of fixed pitch. I saw the same spread on several different props I ran on my Long-EZ. Ideally you should have top end (8000 ft / WOT) RPM of around 2650-2700, which would give you ~75% power at 8000 ft. That gives you the highest cruise speed and with electronic ignition and FI you can lean to get good fuel economy without having to throttle back. That would also give you around 2250 RPM Static. Your current 2080 RPM will definitely cut into your take off performance when you need it the most for Gross Wt, high density altitude operation. R
From my personally experiences, I wouldn't be comfortable with settling for that.

2500 RPM WOT is "nice" for WOT cruise, but you'll suffer top end speed from it also.

FP is a notable compromise on these "high speed range" aircraft.... so you have to decide how you are most often going to operate the plane and understand the associate limitations. If it were my plane, I'd seriously consider re-pitching or blade length to get some more RPM's...

Just my 2 cents...
Click to expand...

I agree 100 percent, Whats interesting Is when I had purchased the propeller from Craig, we had discussed and he said this is the best match for the airplane. Currently I have a 74X70 however when I do searches for the same propller on VAF it seems everyone else has a smaller diameter and lower pitch than mine, Static RPM's for these are closer to 2200. However I did find a Gentelman from Australia with the same combo and he is making the EXACT same numbers as I am. I am going to give it a few more flights and see what happens. We talk that ground role is shorter, but jeez is it still quick. I am going to attemp a little more straight line stuff today and see what numbers I can get.
 
I suppose it's all a matter of weight, expense and complexity which mitigates against a constant speed prop. I guess it is like the glass/steam cockpit argument but I wouldn't pass by the extra efficiencies and benefits of a CS prop. It certainly would have negated some of the issues you have seen. Of course, it may have thrown up other problems........

I'm building a -10 so won't be doing aeros but that would seem to me to be an extra good reason for a CS prop. In the meantime, I am flying Warriors and Arrows with a club. I find the CS prop in the Arrow makes the aircraft much more stable in speed in cruise apart from any other benefits.
 
bkthomps said:
oops :) looks like your brain swapped these
Click to expand...

It sure did, I took it out again yesterday and flew another hour over the airport, the temps are reading much better already. At full throttle and mixture at 3200 ft, cylinders 3 and 4 are both reading 365 and 1 and 2 are reading 380. I think with some modification to the air Dams on 1 and 2 I can bring them all down within a few degrees of each other.

I'm not to happy with the Propeller however, It is a fantastic Cruise prop, once you hit 125kts it will accellerate like you wouldent believe however getting to 125kts takes to long in my eyes. I am going to talk with Craig today and see what we can do to maybe loose a few MPH on the top end but gain it in acceleration and climb.

Overall however, it is a fantastic airplane, simply amazing with what you can do with it.
 
I see in one pic, it appears your gearleg is exposed....do you have all your fairings in place?

As long as you aren't overheating your engine, I wouldnt fuss with prop pitch. Get a little time on the motor then get all the legs and wheels covered up...including upper and lowers. She'll fly different
 
Final conclusion

David, thanks for sharing your experience.

I'm interested to know if while troubleshooting the lack of fuel in cylinder #1, did you guys come across some FOD in that injector or do you think the obstruction just cleared itself.

Thanks.
 
kevinsrv7.com said:
David, thanks for sharing your experience.

I'm interested to know if while troubleshooting the lack of fuel in cylinder #1, did you guys come across some FOD in that injector or do you think the obstruction just cleared itself.

Thanks.
Click to expand...

We were unsuccessful in finding any FOD in the line or injector, however the injector is so small that i doubt you would be able to see it. Also the data shows that it cleared itself and the power came back, it fluctuated a bit when it did come back on line but there was power there.

I put another 2 hours on it tonight without a hitch, the machine is amazing.
 
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