[RV7Guy]

Smart decision!!

Note from moderator:
This thread was seperated from this thread . A new thread was created since the subject matter changed altogether and was worthy of its new title.
End of note.

Jamie,

You made a very wise decision to have someone with significant experience make those first flights. Congrats on the success!!! The event of the first flight is why. Mike's experience allowed him to react instinctively to the issue without concern about how this airplane feels, sounds etc.... He saved the engine, airframe and most importantly, himself because of the experience.

I've mentioned this before and got somewhat flamed for it, but there is a definite attitude with some that, "I built it, I'm going to fly it first." RV's are great planes but when something happens, it happens fast. Unless you have considerable experience in RV's, with proper transition training, I submit that someone else should be doing the first flights.

It is a personal decision but is it? In my case I had nearly 4000 hours of total flight time with recent transition training and a refresher with a friend in his RV7. I still had a very experienced RV pilot (Robbie Attaway) make the first couple of flights. I'm glad I did. The engine monitor went blank shortly after take off. Like Mike, Robbies experience allowed him to fly the plane and safely land instinctively. After the simple fix of the engine monitor Robbie flew the first 1:45 on the plane and I took it over from there.

Sorry for the diatribe but I'm kind of a safety nut and get concerned when I see smart people do less than smart things.

Again, Jamie, congrats. Enjoy that fly off time as you become "one" with your plane.

 

[MNRVFlyer]

Me too

Hi,

I had a similar experience after the rebuild of an engine for a 6A that I purchased flying. I asked Mike Hilger, who gave me my first RV ride, to test fly the plane. Since it was out of phase 1 I went along for the ride. The plan was to fly around the airport for a while and then leave the pattern for a bit. On our second lap we noticed a little oil on the canopy. In about 15 seconds forward visibility was nearly zero as the oil filled the screen. We were upwind getting ready for crosswind when it went bad. Mike made the right decision to continue along and land into the wind (we were at pattern alt, or a little higher). It turns out that the guy who rebuilt the engine forgot to poke a hole in the rear crank seal to let the oil out (it was a hollow crank w/ a FP prop). The oil pressure blew off the front seal. Mike did a great job of saving the engine/plane and our butts. I'm very grateful for his skill. I will be asking him to do my first flight when it's time. In looking back I think I made a mistake in going with him even though it was allowed/legal. I went along to watch for temps/pressures, but I should have stayed on the ground.

 

[dan]

So what was the culprit? The prop oil line at the governor end. The fitting was oh so slightly loose. It never leaked a drop on the ground runs (.8 hrs).

TORQUE SEAL (inspection lacquer) on EVERY FITTING and FASTENER. That way you KNOW it's right. No 2nd guessing.

Jamie, congrats...you & Kahuna done good. Be careful and enjoy that fine airplane!

 

[Jamie]

TORQUE SEAL (inspection lacquer) on EVERY FITTING and FASTENER. That way you KNOW it's right. No 2nd guessing.

I already did this. My engine now looks like it has the orange measles.

 

[TGRV7]

Kahuna, I have a question.
To train for Dead Engine landings with a CS Prop.
Would you practice first with the engine at idle and fine Pitch or Coarse?

Thanks

 

[dan]

Why not test the real thing? Climb up to 10,000' AGL over an airport...cool the engine down a bit...and then pull your purge valve or mixture. Perform actual glide ratio tests with the prop in fine & coarse pitch. See if you can actually affect glide ratio with the prop control. Some people claim they can increase the glide ratio by pulling the prop into coarse pitch. FWIW, I haven't been able to produce those results on my setup.

 

[Kahuna]

Kahuna, I have a question.
To train for Dead Engine landings with a CS Prop.
Would you practice first with the engine at idle and fine Pitch or Coarse?

Thanks

I dont see the value in flying around at idle. You probably do that a lot.
Depending on your prop, being counterweighted or not , and depending on your gov., as to whether or not you can even make a change in pitch at idle.

Moving my prop lever with a windmilling prop changes nothing.

Train for dead stick landing with just that, a dead stick. Do what Dan said. Get up there and play Bob Hoover. Its quite fun really. Turn your RV into a glider and find out how she flies dead. THen make your way to the runway as you get used to the idea and the feel of it. Or better yet, stick someone in your plane with you with experience that can get you over the hump of pulling the red knob and flyihg around Bob Hoover style.

Best,

 

[aadamson]

Comment on this approach to testing glide. I whole heartedly agree with doing it, but most don't do it correctly. You need to go to full Course pitch or full fine pitch with the engine at RPM before you pull the mixture. If you have no oil pressure, you can't move the prop.... That is unless you have a counterweighted one that goes to feather or partial feather on oil pressure reduction, but few do.

If you make that change before you reduce power, you will defiinetly notice a difference in forward glide. If not, you are probably not getting the prop in the angle you expect it to be in.

However with all of this said, in an emergency, most aren't fast enough to get the prop into course pitch before you loose oil pressure. Hence why some opt for the counterweighted prop/gov combo that does it for you automagically - but at a pretty stiff expense.

 

[dan]

You need to go to full Course pitch or full fine pitch with the engine at RPM before you pull the mixture.

Man, that's about as UNREALISTIC as it gets. I mean sure, if you KNOW you're going to have to shut the engine down, go for it, pull the prop then shut 'er down. But seriously. Most cases of proactively shutting the engine down are due to a drop in oil pressure anyway!

In the real life dead stick scenario, you will be in REACT mode, not PROACT. Let's be honest.

If you're gonna train for emergencies, simulate the real thing as closely as you can.

 

[aadamson]

Man, that's about as UNREALISTIC as it gets. I mean sure, if you KNOW you're going to have to shut the engine down, go for it, pull the prop then shut 'er down. But seriously. Most cases of proactively shutting the engine down are due to a drop in oil pressure anyway!

In the real life dead stick scenario, you will be in REACT mode, not PROACT. Let's be honest.

If you're gonna train for emergencies, simulate the real thing as closely as you can.

Dan, I agree with you, but the discussion was about learning what your airplane would do with course vs fine pitch (in fact, in your proposed scenario you offer the following "Perform actual glide ratio tests with the prop in fine & coarse pitch."). In order to do that, you'd have to get to that pitch setting while you have oil pressure. Obviously in an emergency you probably don't have time to react to do that. In fact, the best glide will in fact happen once the prop stops... But that is almost impossible to cause to happen under control that is, once you loose oil pressure ...

Alan

 

[TGRV7]

Thanks guys for your advise.
Question: how many RV pilots do you think practice Dead Stick landings?

 

[az_gila]

FP prop effects...

Man, that's about as UNREALISTIC as it gets. I mean sure, if you KNOW you're going to have to shut the engine down, go for it, pull the prop then shut 'er down. But seriously. Most cases of proactively shutting the engine down are due to a drop in oil pressure anyway!

In the real life dead stick scenario, you will be in REACT mode, not PROACT. Let's be honest.

If you're gonna train for emergencies, simulate the real thing as closely as you can.

Anyone know what happens to a FP RV? When my instructor had me doing dead stick landings in a C-150, the prop wouldn't stop unless the plane was pulled up into a mild stall. Is this true for FP RVs?

Dan suggests over an airport, but the S. Cal. guys should just go out to the Mojave desert and find a nice big dry lake... then you can easily take the landing all of the way to touchdown... It's good enough for the Space Shuttle...

gil in Tucson ... but landed on most of the Mojave dry lakes in my sailplane...

 

[dan]

(in fact, in your proposed scenario you offer the following "Perform actual glide ratio tests with the prop in fine & coarse pitch."). In order to do that, you'd have to get to that pitch setting while you have oil pressure.

That's not quite what I'm saying...I should have clarified. I'm saying do glide tests with the prop CONTROL in both settings to see if it would even make a difference when truly dead stick. i.e. do you even want to bother? I mentioned that it doesn't do diddly in my case, Kahuna corroborated that...although I know some who claim that pulling the prop back to course AFTER pulling the power back to idle (these two guys in particular didn't pull the mixture, they pulled throttle) did in fact improve glide ratio. Again, I don't think it's realistic unless fuel is truly cut off, but that type of test is not for everybody...

 

[Kahuna]

Thanks guys for your advise.
Question: how many RV pilots do you think practice Dead Stick landings?

Very few and not enough.

Anyone know what happens to a FP RV?

This depends completely on the prop. Metal pops are heavier and have a much higher flywheel effect and stay windmilling much longer, to ~ 65kts. Stick props stop pretty fast. Rewindmilling after a stoppage by diving for speed gets even more variable as compressions and weights and lengths all come into play.

On my 6cyl std. compression 2blade hartzell c/s, she stops at ~55kts. I have dove to 200kts and she will not rewindmill on her own. Distance between strokes on rotation of the prop is too short. On my 4 banger c/s she would stop ~65kts, and rewindmill at 120kts. Cause once the prop moved mast a compression stroke, the blade would build up enough momentum to keep going between strokes. My 6 banger wont do that.

On other planes it all depends. 3 blade fixed stays windmilling pretty long down to ~65kts. 2 blade stick on a 4 banger can stop as soon as 100kts. It all depends on many of the factors listed above.

If the goal is to get a feel for the flight characteristics on a dead stick, Ill add that its not enought to just shut down the engine down. You should practice both a windmilling prop and a stopped one. Both cases can happen and the difference in flight charactistics are enough between them that both should be practiced IMHO. In most applications for folks here, you will have to get the plane very slow to stop the prop. A windmilling prop provides quite a bit of drag and a much higher sink rate. It also has a completely different sensation to the body and mind and is worthy of practicing and getting comfortable with. Flying your RV as a glider can be quite rewarding in many ways and you will be a better pilot for it.

Enjoying these important discussions.
Best,

 

[pierre smith]

How??

I appreciate all this good advice but it's not without a caveat.

Mike, would you kindly explain your exact procedure so we avoid guys going off the end of the runway or coming up short....both of which could be disastrous. Do you slip plus use flaps? Flaps only? Kindly explain your method for doing dead sticks successfully. Runway length you'd recommend?

Regards,
Pierre

 

[Kahuna]

I appreciate all this good advice but it's not without a caveat.

Mike, would you kindly explain your exact procedure so we avoid guys going off the end of the runway or coming up short....both of which could be disastrous. Do you slip plus use flaps? Flaps only? Kindly explain your method for doing dead sticks successfully. Runway length you'd recommend?

Regards,
Pierre

Sure. My procedure is a crawl, walk, run approach.
Suitable runway length is at least 5k'. More is better. But this should do.
Start up high, say 4k'agl, or 10k', and just practice gliding around, at idle power, then dead. Do that a few times or until you are comfortable. Yes you CAN get comfortable with a quiet engine, and you should.

Then practice circling approach to runway at better than glide speed. Forget pattern procedures. Its a circle to land approach. ~80kts. No flaps. Flaps should not be deployed until your nearly ready to touchdown. say last 50'agl. Aim for mid field. Tendancy is to always be short with new pilots. Dont think I have ever seen one too long with these planes. On base turn to final look for best glide ~70kts. Always better to be hot and high and slip out the speed you need to bleed away.

In the end, you should be able to put the plane whereever you want it in any configuration. Its like a spot landing contest. I would guess that you could take a glider pilot who has never been in an RV and kill his rv motor and he could hit his spot every time cause he's good at judging what is necessary to hit the spot given the glide condition he is in. And thats the name of the game. You pick a spot and hit it in any configuration. Your dead stick could be cause you are in a dual EI engine and have lost all electrons and have no engine and no flaps. Or it could be lots of other things. I definately do not recommend you use flaps till the very end. I dont like the term "Till you know you have made the field" cause most pilots think they have made the field and when they throw out the drag chute flaps, they are not even close to making it now.

This is the technique that has worked for me. For pilots that have not mastered their spot landings do that first on a long runway. Do it at idle under power till you can hit any spot you desire without touching the power. Paint marks, intersections, and runways lights are good markers. Decide at 2k'agl "Im gonna put it at that intersection right there" and put it to idle under power and hit it. I mean nail it every time. Then work towards a very short strip. Havent landed at a very short strip with trees and obstacles? Go find one and work your way towards that too. You IFR rated guys, ever played dead stick under the hood? Talk about hard to hit the runway. Its very hard under the hood. Grab a safety pilot and go try. Learn your glide speed and distances from the target. Good news for us RV'ers is that hot and high, and we can drop like a rock to hit a spot.

When the unplanned dead stick happens, it is of tremendous comfort to know you can put that plane exactly where you wanted it when the options are limited.

All of this work can be fun and rewarding. It can be done safely if its controlled and worked towards gradually. Its way better than just zipping around the patch for no reason other than to put air under the wings. Also there are a bunch of skilled RV'ers who are happy to jump in your plane with you and help you explore this facet of the RV envelope. In a single engine experimental, Im convinced this is required skill for long term piloting success and survival.

Many of the readers are thinking "Oh my god he is advocating pilots go kill their engines." Well thats true. If its not for you then dont do it. If you have no interest in learning how to fly your plane dead stick cause it wont happen to you then disregard everything here.

I have found this to be an excellent traing and survival tool. Pilots I have worked with initially are sweating bullets when the fan stops, but eventually really feel good about themselves and their new ability to handle the future stressful dead stick. And I have no doubt that i and they will be able to handle it when the time comes. And it will come for many.

Ok I have ranted enough.
Best,

 

[Geico266]

I could not agree more about dead stick practice.

When I got my ultralight (pre-sport pilot) licence, then became an ultralight instructor we had to complete 3 successful dead sticks (no windmilling) and make it to the middle of a 2,500' field. It came in handy as I have had 3 actual dead stick landings flying 2 stroke engines. The dead stick landings were really non-events due to this training. Flying 2 strokes, it's just a matter of when the engine quits, not if.

I haven't practiced a dead stick in an RV. Getting lazy I guess, time to get with it and see how I do. Thanks for the great info.

Any thoughts about shock cooling and how to avoid it?

Great thread!

 

[Stogie 6]

Dead Stick and Engine Out Procedures

WOW....

As I read the previous posts about Jamie's first flight, I was reminded of my father flying a friend's RV6-A. He was the second to take it up and this same issue happened. That plug in the rear of the block came out and the break-in mineral oil covered the windscreen. He shut it down and dead stick'd it in for a beautiful landing. We all were there and didn't even realized he was back due to the fact that the engine was not running and we did not hear the return. I guess we were too busy talking to the test pilot.

Now, my heart is pumping with the thought of getting dead stick training. I usually will sit on my hand to keep it off the throttle. I have always wondered what an engine out really feels like?

Thanks for the information and post about this subject. I am off to the field to find and schedule time with my instructor.

Heart's still pounding and I am just thinking about it!

WOW!

 

[Kevin Horton]

Well done to Jamie for making a good decision on who should fly the first flight, and to Mike for a well handled incident.

Thanks to Jamie and Mike for sharing this info. It is a great example of why the pilot for the test flights should be mentally prepared to deal with the unexpected, current in RVs, and have good flying skills. Yes, there is only a small chance that something will occur where having the right pilot would make a difference. But, if that event does occur, having the right pilot could make the difference between a "non-event", and a fatal accident, or severely damaged aircraft and/or engine.

 

[kentb]

So....

To optimize glide distance with the engine dead, should you first pull the plane up as much as needed to stop the prop before setting up for best glide?

Kent

 

[Dgamble]

I recently had the opportunity to learn what it feels like in my 6 to have the engine out. It was accidental, which doesn't reflect well on me, but it was for sure a valuable lesson. I'll recognize the problem much sooner if it happens again.

Lesson 2 is that if you want to get a lot of hits on your blog, title a post "I Learned About Being a Dumba$$ From That" - literally hundreds of hits. Big trip report (http://n466pg.blogspot.com/2007/07/co-pilot-egg-and-tour-of-uss-cod.html) on Burke-Lakefront, not so much. Sigh. So goes blogging.

Here's the link for the ten people that missed it:

http://n466pg.blogspot.com/2007/07/test.html

 

[videobobk]

I, too, had three deadsticks in an U/L. Also almost one in a Cessna (the carb ice cleared at about 100', BIG lesson.) By 15 hours into Phase One I tried the big red knob pull. I learned how much altitude I would lose in differently banked turns both windmilling and prop-stopped. As my idle is set very low, there is little difference between pulled throttle and pulled mixture, but there is enough that I need the practice in dead stick. I am scheduling some dead stick landings on my next few flights, just in case. Thanks for the reminder, Kahuna.

BTW, my three-blade Catto will restart at somewhere around 130 mph. Never really watched the airspeed that closely, and usually the switch was easier. Tighter banked turns cost less altitude per full turn, at least in my 9A.

Bob Kelly

 

[dan]

To optimize glide distance with the engine dead, should you first pull the plane up as much as needed to stop the prop before setting up for best glide?

Kent

Test it out BOTH WAYS in YOUR airplane. That way you don't have to GUESS when you have the real situation.

I did stopped-prop testing in my RV-7. To get the prop to stop windmilling, I had to pull the nose up to like 60 MIAS. I then pushed the nose over to best glide, which in my airplane is right around 100 MIAS. Anything over 85 MIAS and the prop would start moving, and over 90 it was windmilling again.

To me, in MY AIRPLANE (I don't speak for you & your airplane) stopping the prop is COUNTERPRODUCTIVE in more ways than one.

 

[dan]

I did stopped-prop testing in my RV-7. To get the prop to stop windmilling, I had to pull the nose up to like 60 MIAS. I then pushed the nose over to best glide, which in my airplane is right around 100 MIAS. Anything over 85 MIAS and the prop would start moving, and over 90 it was windmilling again.

I should also mention that this was with the throttle around 3/4 open. I forgot to test it with the throttle closed but I plan to do that at some point.

I do believe throttle position comes into play when determining the speed at which the prop will start to windmill again. I don't have data to back that up...just a theory. Something else to test on YOUR AIRCRAFT/ENGINE if you do these tests.

 

[Kevin Horton]

I should also mention that this was with the throttle around 3/4 open. I forgot to test it with the throttle closed but I plan to do that at some point.

I do believe throttle position comes into play when determining the speed at which the prop will start to windmill again. I don't have data to back that up...just a theory. Something else to test on YOUR AIRCRAFT/ENGINE if you do these tests.

In theory, once the combustion stops, it will take more hp to spin the engine if the throttle is open than if it is closed. That is because there is more air being pumped through the cylinders with the throttle open, and it takes more hp to compress all that air on the compression strokes. So, if the prop is windmilling and driving the engine, the prop will be more likely to stop if the throttle is full open than if the throttle is at idle.

Once the prop is stopped, and you increase the speed to try to get it windmilling again, the amount of air in the cylinders will be same no matter where the throttle is. So, it should start to turn at the same speed, no matter what the throttle position is. But, once it starts to turn, having the throttle at idle will assist in get it up to full windmilling speed quicker (but this will also increase the windmilling drag, which will hurt glide performance).

 

[Kevin Horton]

To optimize glide distance with the engine dead, should you first pull the plane up as much as needed to stop the prop before setting up for best glide?

Kent

If you have lots of altitude, and you know (from previous flight testing) that it should be possible to get the prop to stop if you slow down, and you know (again, from previous flight testing) that the prop will stay stopped at best glide speed and a bit faster, then it may be worthwhile to slow down to stop the prop. Pushing the throttle full open should help the prop stop (see my previous post for more on this).

If you stop the prop, and later on push the nose over because you are above the desired glide profile, there is a risk that the prop will start to spin. If this happens, there will be a big increase in drag, and big decrease in glide performance. This could be a very nasty surprise if it happened late in the forced landing pattern. For this reason, I would be hesitant to stop the prop unless previous flight testing had showed that you would have a good speed range to work with before it started windmilling again.

If you are at low altitude, don't screw around trying to stop the prop. Just fly the aircraft.

If you haven't actually previously stopped the prop during a flight test, an actual engine failure is probably not the right time to try to get that data point. Trying to stop the prop could become a distraction from just flying the aircraft, and cause you to screw up the forced landing profile, or you might stall the aircraft. Just accept the glide performance you have and fly the aircraft all the way to the ground.

The best glide speed, and the glide ratio at best glide speed, will be different depending on whether the engine is at idle, stopped with a windmilling prop, or stopped with the prop stopped.

 

[rv6ejguy]

Pumping losses are much greater with closed throttle than open throttle. Stopping the prop would be best accomplished with closed throttle. Extending the glide if the prop will not stop should be assisted by going WOT.

 

[Kevin Horton]

Pumping losses are much greater with closed throttle than open throttle. Stopping the prop would be best accomplished with closed throttle. Extending the glide if the prop will not stop should be assisted by going WOT.

This is true if the engine is running, and we are looking at the pumping losses through the throttle plate. But, if combustion has stopped, and the engine is being driven by the prop, the higher the MP the more torque it takes to push the engine over the compression stroke. If you don't believe this, conduct a small thought experiment - how would the torque required to spin the engine vary if the MP was reduced to zero, so there was no air in the cylinder to compress - i.e the engine was in a vacuum? Can we agree that the torque required to get over top dead centre will vary with MP?

The MP will be higher if the throttle is open than if it is closed. As we slow down, the torque that the prop can generate will decrease. At some magic speed the torque available from the prop will be less than the torque required to push the piston over the top of the compression stroke, and the prop will slow down, then stop.

Mind you, all the above is based on theory. I don't have any actual flight test data to confirm the theory. I'd welcome any comments from anyone who has actually flight tested this.

 

[rv6ejguy]

Myths Busted?

Thanks Kevin for bringing up the topic.

Nothing like a little real life experimentation to prove or disprove theories.

I drove 2 cars here ('84 Supra shop beater and '89 turbo 240SX shop rocket) on the same stretch of road, same gear, same speed. Shut off both engines and measured the time taken to decelerate from 100 to 80 kph with both WOT and closed throttle. Surprise, no appreciable difference in time. Both cars mirrored responses.

This might explain why Dan said he saw no difference in WOT or closed throttle glide performance.

I started thinking why. My theory is that with engines having cams of about equal intake and exhaust duration, closed throttle causes nearly equal losses on the intake stroke as open throttle does on the compression stroke.

It would seem from this that the throttle position has little to do with either stopping the prop more rapidly or extending the glide. Interesting that some flight manuals suggest to go WOT to extend the glide.

I agree that practicing engine out stuff will aid you when the real situation hits.

Unfortunately you'll probably find that you sometimes don't have a suitable field or runway underneath you when the fan quits. Your options may be limited. Aim for the best spot. You may then find that the area you picked at 1000 or 2000 AGL looks very different at 150 feet- fences, trenches, bushes, rocks etc. All you can do at this point is to ride it down for those last few seconds and avoid the nasty stuff.

Biggest thing to remember is not to stall the aircraft. I can assure you that the natural self preservation reaction is to pull to avoid obstacles. Fight not to do this. Accept that you are going down and fly it right down to impact.

 

[dan]

This might explain why Dan said he saw no difference in WOT or closed throttle glide performance.

I didn't say that. I said I didn't see any difference in glide ratio based on moving the prop control to coarse pitch (after the engine had already lost power).

 

[videobobk]

Something to contemplate as you look for a "suitable field."

Pumping losses are much greater with closed throttle than open throttle. Stopping the prop would be best accomplished with closed throttle. Extending the glide if the prop will not stop should be assisted by going WOT.

Russ is right here. While there is more air to compress (compression stroke) when the throttle is open, there is also more compressed air to push the prop on through the power stroke. These forces (leakage past rings and valves excepted) are equal, regardless of throttle setting. The difference is how much vacuum the engine has to work against on the intake stroke. It is considerably higher when the throttle is closed. Theory aside, all this makes very little difference when things get really quiet up front. Stopping the prop shouldn't be done unless you have lots of altitude, then you probably don't need to anyway.

Bob Kelly

 

[Kevin Horton]

Russ is right here. While there is more air to compress (compression stroke) when the throttle is open, there is also more compressed air to push the prop on through the power stroke. These forces (leakage past rings and valves excepted) are equal, regardless of throttle setting. The difference is how much vacuum the engine has to work against on the intake stroke. It is considerably higher when the throttle is closed. Theory aside, all this makes very little difference when things get really quiet up front. Stopping the prop shouldn't be done unless you have lots of altitude, then you probably don't need to anyway.

Bob Kelly

OK - I hadn't properly considered some of the factors that are at play here. I'll certainly concede the possibility that Russ may be right. I don't think his car test had good enough resolution to really see small differences though.

This is something that I will eventually flight test, and I expect a flight test should be able to see much smaller differences than could be seen in his car. I should be able to nail down within a knot or two at what speed the prop will stop with throttle open, and with throttle closed. I'll eventually report the results.

 

[n5lp]

... I should be able to nail down within a knot or two at what speed the prop will stop with throttle open, and with throttle closed. I'll eventually report the results.

When I did a little testing of this, I found another variable. The speed the propeller stopped and started at seemed to have quite a bit to do with how warm the cylinders were. Not much of a factor in real life but it is a factor when you are doing testing where you glide engine off for a significant time.

 

[rv6ejguy]

I didn't say that. I said I didn't see any difference in glide ratio based on moving the prop control to coarse pitch (after the engine had already lost power).

Ooops. Sorry Dan, didn't re-read your post. Do you see any difference in decent rate at WOT vs. closed throttle?

The resolution of the car test was pretty good I think with a stop watch and good ground speed measurement (speedo). Probably much harder to get better data in an aircraft. There may indeed be a slight difference but you have more things to worry about in this situation than a possible few percent in glide ratio. It would seem than 2-3 knots in airspeed will have a larger effect on glide ratio than the throttle position.

 

[dan]

Ooops. Sorry Dan, didn't re-read your post. Do you see any difference in decent rate at WOT vs. closed throttle?

I'll quote myself this time...

I should also mention that this was with the throttle around 3/4 open. I forgot to test it with the throttle closed but I plan to do that at some point.

I do believe throttle position comes into play when determining the speed at which the prop will start to windmill again. I don't have data to back that up...just a theory. Something else to test on YOUR AIRCRAFT/ENGINE if you do these tests.

 

[Yukon]

Risk / Reward

I'm not really sure what the point is of all this "throttle open, throttle closed, prop stopped, prop not stopped" is. If you have winds on the day of your engine out, you can't control or predict the value of head or tail winds in the glide, so I think our time would be better spent practicing glide path judgement rather than trying to predict the the glide angle.

Another thing to think about........spin training used to be mandatory for licensing, until the Feds discovered that more people were being killed in spin training than in spin accidents. Airlines used to do engine-out training in their aircraft, now pretty much unheard of due to many nasty training accidents.
Simulators now provide this experience, risk-free.

We as a group must strive to make our training as safe as possible. Stopping the prop on a high-wing loading airplane, on purpose, is a needless risk. You won't be able to windmill re-start it, and sure as the world, that will be the day your starter will glitch on you and there you are with a real emergency on your hands. Also, supercooled cylinders, shrinking around hot pistons and rings almost guarantee a hard start for the starter when the time comes.

Find your zero-thrust power setting and practice your glide judgement all day long virtually risk-free. Also, do a power recovery from the glide at 1000 feet, then 500 feet, 300 feet, and when you are getting really good AND comfortable, you can consider taking it to the runway. Also, don't forget after about 45 seconds of gliding, you carbed guys will have very little carb heat available, so a little throttle burst once in a while will keep the carb heat active.

Don't let the cure be worse than the disease. Practice engine-outs safely.

 

[dan]

Yukon, I could not agree with you more. Well said.

I wouldn't discourage anybody from "trying" any of this stuff, as long as it's done safely.

 

[n5lp]

I'm not really sure what the point is of all this "throttle open, throttle closed, prop stopped, prop not stopped" is. If you have winds on the day of your engine out, you can't control or predict the value of head or tail winds in the glide, so I think our time would be better spent practicing glide path judgement rather than trying to predict the the glide angle.

I think that is a pretty good point. There are so many variables that this type of testing probably doesn't have a lot of value.

We as a group must strive to make our training as safe as possible. Stopping the prop on a high-wing loading airplane, on purpose, is a needless risk. You won't be able to windmill re-start it, and sure as the world, that will be the day your starter will glitch on you and there you are with a real emergency on your hands. Also, supercooled cylinders, shrinking around hot pistons and rings almost guarantee a hard start for the starter when the time comes.

Now some of this isn't true for my airplane. I know because I have tested it. I know it is hard to stop the prop and know what speed it takes to start the engine by diving. I also know it is not hard to crank the engine with the starter. High wing loading is a subjective thing, but I consider the RV to be a low wing loading airplane, especially for its performance. It does have a wing design that produces fairly high drag a low speeds.

I would never recommend someone do engine off testing, but I did it and was very comfortable including a glide to touchdown. I wasn't near as comfortable pulling 6 Gs in a test, which I would consider mandatory for anyone who is going to do aerobatics.

Interesting to watch the prop slow to a stop on final.

 

[Yukon]

Fly Safe Guys

Yes indeed Larry, high-time pilots like you, Dan and Kahouna can and do get away with this kind of stuff. My concerns are for the 100-500 hr guy that will
be trying it if encouraged to do so. Way too much risk for the newbie.

The stupid $hit I did at 200 hrs would make your head spin. Amazing that I am still here!

 

[rv6ejguy]

I'm with Yukon on this one. Not a fan of shutting it down for practice. The wind thing will throw off all your plans. Best to judge where you will make it to by what appears stationary in the windshield at best glide speed.

Don't count on having electric flaps available if you arrive too high. Practice slipping instead.

I find many pilots are overconfident that they can "get it down safely" if the engine quits. That's great if you have flat pastures, roads or a runway below. You will damage the airplane on plowed fields or rocks and risk flipping over and possibly being trapped as well.

The real emergency will be a lot different than the practice in many cases.

Practice is good but don't become a statistic doing it.

 

[RVbySDI]

evaluation of risk based on experience

Yes indeed Larry, high-time pilots like you, Dan and Kahouna can and do get away with this kind of stuff. My concerns are for the 100-500 hr guy that will
be trying it if encouraged to do so. Way too much risk for the newbie.

The stupid $hit I did at 200 hrs would make your head spin. Amazing that I am still here!

Ok, guys. You can call me a newbie, a wimp, a woose, a chicken, a novice. Call me whatever you want but the reality is the level of risk of purposefully doing these type of maneuvers as a 100-500 hour guy is different than the level of risk you experts out there with all that experience are dealing with.

Yukon is right. He is right because risk is only controlled by attention to detail by anyone who is placed in a risky situation. Attention to detail is achieved when one has enough experience with the situation to be calm enough in the situation to be able to think about the important things and disregard the non-essential things. An experienced person has learned through his/her experiences what is necessary to think about and then to act upon those thoughts in order to minimize the risk. This experience provides necessary capabilities that I will have not acquired as a newbie, novice, wimp, woose or chicken. Therefore my risk of doing these maneuvers will be much greater than yours.

With experience comes clarity of thought. With clarity of thought comes logical reasoning. With logical reasoning comes wisdom. With wisdom comes efficiency of motion. With efficiency of motion comes a controlled environment. With a controlled environment comes minimization of risk.

It is indeed a bit of a catch 22 situation. One cannot gain experience in hopes of gaining control of the situation unless it is felt the risks have been minimized to a comfortable enough level to be able to deal with a risky situation. But one cannot deal with the risk until one has enough experience to feel comfortable enough that he/she can maintain some level of control of the situation.

Minimize the risk and you can push the envelope to learn something new. Push the envelope and you can gain new experiences. All of it is a balancing act around that level of risk taken. Experience is that one very valuable thing that does the most to minimize the risks we take. Practice is a proven way to gain experience but the key to successful practice here is in that act of controlling the risk taken during the practice.

I aspire to obtain the greatest level of experience I can in order to fly as safely as I can. However, at my present level of experience, I cannot look at performing these maneuvers without developing a great amount of anxiety and fear. This anxiety is coming from having the experience of two real engine failures that resulted in two very real and very scary dead stick landings off field. The first incident I am lucky to survive. The second, because of my experience with the first, I had the presence of mind to be able to think my way through the emergency clear down to the ground.

Even after these experiences I do not feel experienced enough to purposefully repeat them unless I spend a great deal more time analyzing the nuances of controlling that emergency environment and therefore minimizing the risk.

Live Long and Prosper!

 

[WSBuilder]

Youth isn't always wasted on the young

I did most of my stupid risk-taking stuff in my first 500 hours. The second 500 where boring by comparison. So when did I get the EXPERIENCE: 1-500 or 501 to 1000?

 

[Yukon]

1-1000. It's all good!

 

[johnp]

And the safe way to expand ones knowledge without beeing to close to danger because of to little experience, is often by flying with an experienced and skilled instructor

you still have to stretch your comfort zone at times. you could be perfectly comfortable doing something with the instructor in the seat beside you, but still uncomfortable solo. the real trick is to have a plan B for when things go pear-shaped, and not be too reluctant to use it. (how do you think the instructors got their experience?)

 

[Kevin Horton]

I did most of my stupid risk-taking stuff in my first 500 hours. The second 500 where boring by comparison. So when did I get the EXPERIENCE: 1-500 or 501 to 1000?

You develop good judgement from experience. You develop experience from bad judgement. A very few are smart enough to get experience based on learning from other people's bad judgement, but most of us are stupid enough to try all the stupid stuff at least once ourselves.

You start your flying career with two bags - a full one labeled "Luck", and an empty one labeled "Judgement". The key to longevity is to get the second bag filled up before the first bag comes up empty when you need it. It scares the heck out of me to think about some of the stuff I used to do back when I was young and immortal .

 

[Hostage46]

There is a safe way to get power off training...

Yukons' comments on low time pilot concerns are valid. One inexpensive and safe option for dead stick training is to get your glider endorsement. At a minimum get to solo.

Nothing get's your mindset squared away better on a dead stick landing then releasing from the tow plane!

Yes I know an old 2-32 is not the same as an RV, but you will learn a lot.

Plus glider folk are fun to hang out with! In general, it's pretty inexpensive to get some time in the saddle, you won't be disappointed.

Dan

 

[Mel]

You think an RV is different from a 2-32, I owned a Globe Swift when I was taking glider training. Quite a difference in glide ratio. Although, except for the speeds, wheel landing a Swift is quite a bit like landing a 2-32.

 

[David-aviator]

The Feds frown on deliberate engine shut downs SEL or MEL for the same reason they did away with spin training for everyone except CFI's. People get killed filling those squares. FAA inspectors have bit the dust during check rides, that may be why the current policy is what it is.

Dead stick training, with or without the engine shut down, is OK stuff to practice but the proof of the pudding when it happens for real is all mental. He who plans on an engine failure with every flight will do better than the guy who doesn't believe it will happen. It won't be quite such a surprise and surprise is what locks up the brain which sometimes ends down with a stall spin.

If it happens at 10,500 you've got all day set up and do your little check list. If it happens at 1000 AGL, you've got about 1 minute in an RV. That's the one you've got to be mentally prepared to deal with. If you are going to practice dead sticking, do it for that one. And the place to do it is from downwind or base leg as frequently as you can. Pull the power to idle and see where you end up. The engine doesn't have to be shut down, the wind will provide enough variance in glide distance from day to day to get a feel for how things will turn out.

It is impossible to guarantee a practice visual picture when it happens for real. You don't know what the wind will be, how heavy the airplane will be, whether or not the prop is windmilling or what the landing site will look like. The important thing about doing it though is to condition your brain to deal with whatever happens. That is the greatest challenge flying a SEL experimental airplane. The low altitude engine failure requires an immediate plan. It has to be embedded like ROM in a computer.

I've had 2 bad days flying these things, one from 10,500 and one from 1000' AGL. The 1000' foot event went from fat, dumb and happy to "oh shxx" in about 2 seconds as the prop stopped and about 45 seconds to terra firma. The brain says switch fuel tanks, try the starter, get the thing running, etc. but a deeper embedded program suddenly surfaces and says, FLY THE AIRPLANE. That's the one that will save the day if it can be saved, fly the darn airplane.

It behooves each pilot, no matter what your experience, to have a plan for the low altitude event. Flying these machines is fun, but there is more risk than most pilots appreciate.

 

[az_gila]

Gliders...

You think an RV is different from a 2-32, I owned a Globe Swift when I was taking glider training. Quite a difference in glide ratio. Although, except for the speeds, wheel landing a Swift is quite a bit like landing a 2-32.

Mel... practising with a glider with the dive brakes open would be a first start.

A 2-33 (not the better 2-32) is a claimed 23:1 glide ratio - realistically it's about 4 miles per 1000 ft. Fly it faster, and it probably gets close the the RV glide angle (IIRC, about 1.5 miles per 1000 ft).... crack open the dive brakes and it's there.....

Do this in a glider, and if you get in a bad spot, close the brakes and slow down to best L/D and make the field...

This would be a safe way with an instructor of visualizing glide angles and circuits...

gil in Tucson

 

[dan]

Ehhh, you sailplane guys... Last time I "practiced" in a 2-33 (June), I ended up "stuck" at 12,700' and had to use dive brakes just to get home for dinner.

There's no comparison. Trust me, a low-end glider flown dirty and sloppily (i.e. by a noob like me) doesn't even come close. The short wing RVs glide like the proverbial set of car keys! Especially with a c/s prop.

Ok, now everybody is probably running out to buy long wing RVs and sell their C/S props...have fun!