Love At First Sight

Most of the Rvs have a Van's or Plane Power internal regulated alternator. They need a blast tube to them to keep them cool. I had problems with my 7 until I did that and no issues since. Don

I've got a B&C alterntor in mine and have never had a charging problem (8XX hours). Neither have any of the other ~10 or so RV's on my field, regardless of which alternator they have. Not sure this is a common problem..

Vapor lock on a hot day, on the other hand.... ;-)
 
Jay - how long did it take from the day you decided to buy an experimental to the day Amelia arrived at your hangar? I think I missed the thread where you decided, but I do recall you mulling it over.

We've been planning for this day since we bought the trailer we keep in OSH three years ago, preloaded with our camping gear.

I seriously stated looking in February. We rejected several planes between then and May.
 
I've got a B&C alterntor in mine and have never had a charging problem (8XX hours). Neither have any of the other ~10 or so RV's on my field, regardless of which alternator they have. Not sure this is a common problem..

Vapor lock on a hot day, on the other hand.... ;-)

The suspect voltage regulator is mounted in the engine compartment, on the firewall. As you can imagine, it's like the gates of hell hot in there.

A new one is $27. I'm going to mount it in the forward luggage bay, on the opposite side of the firewall. That should resolve our issue, I hope.

Although we spent all day doing transition training, in 94 degree heat, and it was fine -- so go figure?
 
The suspect voltage regulator is mounted in the engine compartment, on the firewall. As you can imagine, it's like the gates of hell hot in there.

A new one is $27. I'm going to mount it in the forward luggage bay, on the opposite side of the firewall. That should resolve our issue, I hope.

Although we spent all day doing transition training, in 94 degree heat, and it was fine -- so go figure?

It's "gates of hell hot" under every cowl. And many voltage regulators are mounted to firewalls.

What's the temp rating on your regulator? I can't imagine yours is being subjected to anything worse than mine. The 182 isn't known for being cool running with beautiful airflow under the cowl. ;)

We've had one fail in six years. None prior to that in the logs.

Is the problem really the location, or just the quality of the regulator?

Just asking the obvious to save you drilling a bunch of holes in your firewall, if a slightly higher priced part would also address the problem.

Seems like maybe you're just wanting to do something major just because its an EAB and you can...

Just checking that you're not planning a complete re-engijeering project for something a $50 part instead of a $27 part will fix. ;)
 
It's "gates of hell hot" under every cowl. And many voltage regulators are mounted to firewalls.

What's the temp rating on your regulator? I can't imagine yours is being subjected to anything worse than mine. The 182 isn't known for being cool running with beautiful airflow under the cowl. ;)

We've had one fail in six years. None prior to that in the logs.

Is the problem really the location, or just the quality of the regulator?

Just asking the obvious to save you drilling a bunch of holes in your firewall, if a slightly higher priced part would also address the problem.

Seems like maybe you're just wanting to do something major just because its an EAB and you can...

Just checking that you're not planning a complete re-engijeering project for something a $50 part instead of a $27 part will fix. ;)

Good point. However, an RV is much more tightly cowled than a 182, or my Pathfinder. The way this thing goes offline intermittently, it sure points to heat as the issue.

Of course, a new part could last ten years in there. Who knows?

Right now, it's working, so I'm not gonna do anything.
 
Would it be unreasonable to mount a spare and a switch for a back up unit?
 
Good point. However, an RV is much more tightly cowled than a 182, or my Pathfinder. The way this thing goes offline intermittently, it sure points to heat as the issue.

Of course, a new part could last ten years in there. Who knows?

Right now, it's working, so I'm not gonna do anything.

Or a broken wire. ;)
 

Flight report, eh? First, another picture, of Mary coming back with Tom last night.

1016600_539325059436726_635125876_n.jpg


This plane will do anything you ask of her. You first must learn her language, but once you've done so, she is a kitten. Making her purr is fun!

On today's 2-hour training hop, I did a 6500' deadstick spiral to a spot landing, lots of power on and power off stalls, and I even landed her from the back seat!

This last one raised Tom's eyebrows a bit, but my reasoning was that I will be spending half of my life back there, and I'd like to verify that those controls I paid big bucks to install were worth it.

I now know that not only is it possible to land from back there, it's fun. Without brakes, you can't steer on the ground, but if the front seat pilot becomes incapacitated, it's no big deal to get back on the ground.

After a two hour break, to let the heating of the day peak, we're headed back out. I need 1.3 more hours to make the insurance gods happy, but I feel like I'm ready for prime time now.
 
Or a broken wire. ;)

Tom has spent too many hours chasing THAT possibility. We ALL thought it was a broken wire, at first.

And it may still be. Wires broken inside the insulation aren't unheard of. All we know is that it's intermittent, and has NOT failed now in the last three flights. That's 5 hours of VERY hard flying.
 
More detail:

Stalls
The RV-8A stalls in the lower 50s. Due to a non-standard static port, this one indicates 63 knots at the break. This is not uncommon, and we have verified that it is instrument error, not airframe related. The plane stalls where and like it should, and the 63 knot number is repeatable, so it really doesn't matter -- as long as you know where to expect it.

Power off stalls are benign, with a good shudder warning you of what's to come. It's easy to make it break either direction by just placing your foot on either rudder pedal. It's just as easy to make it break straight ahead.

A secondary stall is easy to induce after recovery, and it's a bit more wicked, but still nothing pushing forward on the stick won't cure.

Power on stalls are incredible. You can't do them above 22 inches of manifold pressure, or it will be a hammerhead stall. Even at 22 inches, your deck angle exceeds 60 degrees up, which feels amazing.

They, too, are benign, and easily recoverable. And way, way fun.

Departure
Differential steering is different, but has many advantages in ground handling. You can pull this plane FORWARD into my hangar, and turn it 180 degrees around, like a tank. Too cool.

On takeoff, you must apply power slowly, or the P-factor is immense. A big foot full of right rudder helps, but don't shove the power in all at once, or you'll regret it.

As speed picks up, you've got the stick all the way back. As the nose gets light, slowly push forward, letting the force off the stick. Not too much, not too little, and then it just flies off nicely. Pull back too hard, and you'll pop off and results are exciting.

This thing has incredible rudder and elevator authority, so TINY inputs are rewarded. Start pushing and pulling, and it gets a bit too exciting!

You normally take off without flaps. The power-to-weight ratio is great, so there's no need for them. I tried one with 15 degrees of flap, just because, and we were off the ground incredibly fast. It was hard to not exceed flap extension speed, so I don't think we'll need to try that again any time soon.

Cruise
Cruise flight is wonderful. The cockpit has plenty of room, and the visibility is INCREDIBLE. The plane is fast, efficient, and so incredibly responsive. If you've ever ridden a Suzuki sportbike, you know how it does whatever you think. This plane is the same, WITHOUT being twitchy.

Once you learn not to fly it like a Cherokee, that is. Think fingers and toes, not hands and feet.

Landing
It is very un-spam can like to land an RV-8A. First of all, if Cherokees drop like bricks, RV-8s drop like bricks with anvils on them. We always joke that "You're never too high in a Pathfinder". Well, multiply that by ten in the RV.

This is unnerving, at first, but with practice becomes useful. You simply plan a steeper approach, and round out at the end to a nice, smooth landing.

We've been using 85 knots indicated as a good pattern speed. Flap application is pretty standard, and extension speed is 95 knots, so it's not a worry. Slowing down to 85 knots took a bit of practice, but those short wings and enormous sink rate can be converted to speed reduction easily by simply chopping power and raising the nose as lift diminishes. You can go from 120 to 85 in a blink, with practice.

We do half flaps abeam the numbers, full flaps on base. The electric flaps have no detent or markings, so you simply look at the flap and say "That looks about right".

At first, the landing sight picture is absolutely bizarre. You literally fly this thing down to the runway in what feels like a nose-down attitude, and then round out to land. If you raise the nose on final, like we do in the Pathfinder, the sink rate can be impressive, so you don't do it that way.

The ONE thing our instructor has yelled about (to me, anyway) is "KEEP YOUR HANDS STILL". Because of the push-pull tubes controls connected to the large control surfaces, if you slide down final approach making your usual small corrections (as you do when landing any spam can), the plane becomes twitchy as it follows your every move.

Once you learn to calm your hands, it is rock solid stable on final, and squeakers are easy.
 
Last edited:
Tom has spent too many hours chasing THAT possibility. We ALL thought it was a broken wire, at first.

And it may still be. Wires broken inside the insulation aren't unheard of. All we know is that it's intermittent, and has NOT failed now in the last three flights. That's 5 hours of VERY hard flying.

I HATE intermittent electrical problems...:yes::mad::mad::mad:
 
Wow, neat to see your comparisons to Piper. Maybe you should be a test pilot / plane review person! Your test flights sound awesome.
 
More detail:

Stalls
The RV-8A stalls in the lower 50s. Due to a non-standard static port, this one indicates 63 knots at the break. This is not uncommon, and we have verified that it is instrument error, not airframe related. The plane stalls where and like it should, and the 63 knot number is repeatable, so it really doesn't matter -- as long as you know where to expect it.

Power off stalls are benign, with a good shudder warning you of what's to come. It's easy to make it break either direction by just placing your foot on either rudder pedal. It's just as easy to make it break straight ahead.

A secondary stall is easy to induce after recovery, and it's a bit more wicked, but still nothing pushing forward on the stick won't cure.

Power on stalls are incredible. You can't do them above 22 inches of manifold pressure, or it will be a hammerhead stall. Even at 22 inches, your deck angle exceeds 60 degrees up, which feels amazing.

They, too, are benign, and easily recoverable. And way, way fun.

Departure
Differential steering is different, but has many advantages in ground handling. You can pull this plane FORWARD into my hangar, and turn it 180 degrees around, like a tank. Too cool.

On takeoff, you must apply power slowly, or the P-factor is immense. A big foot full of right rudder helps, but don't shove the power in all at once, or you'll regret it.

As speed picks up, you've got the stick all the way back. As the nose gets light, slowly push forward, letting the force off the stick. Not too much, not too little, and then it just flies off nicely. Pull back too hard, and you'll pop off and results are exciting.

This thing has incredible rudder and elevator authority, so TINY inputs are rewarded. Start pushing and pulling, and it gets a bit too exciting!

You normally take off without flaps. The power-to-weight ratio is great, so there's no need for them. I tried one with 15 degrees of flap, just because, and we were off the ground incredibly fast. It was hard to not exceed flap extension speed, so I don't think we'll need to try that again any time soon.

Cruise
Cruise flight is wonderful. The cockpit has plenty of room, and the visibility is INCREDIBLE. The plane is fast, efficient, and so incredibly responsive. If you've ever ridden a Suzuki sportbike, you know how it does whatever you think. This plane is the same, WITHOUT being twitchy.

Once you learn not to fly it like a Cherokee, that is. Think fingers and toes, not hands and feet.

Landing
It is very un-spam can like to land an RV-8A. First of all, if Cherokees drop like bricks, RV-8s drop like bricks with anvils on them. We always joke that "You're never too high in a Pathfinder". Well, multiply that by ten in the RV.

This is unnerving, at first, but with practice becomes useful. You simply plan a steeper approach, and round out at the end to a nice, smooth landing.

We've been using 85 knots indicated as a good pattern speed. Flap application is pretty standard, and extension speed is 95 knots, so it's not a worry. Slowing down to 85 knots took a bit of practice, but those short wings and enormous sink rate can be converted to speed reduction easily by simply chopping power and raising the nose as lift diminishes. You can go from 120 to 85 in a blink, with practice.

We do half flaps abeam the numbers, full flaps on base. The electric flaps have no detent or markings, so you simply look at the flap and say "That looks about right".

At first, the landing sight picture is absolutely bizarre. You literally fly this thing down to the runway in what feels like a nose-down attitude, and then round out to land. If you raise the nose on final, like we do in the Pathfinder, the sink rate can be impressive, so you don't do it that way.

The ONE thing our instructor has yelled about (to me, anyway) is "KEEP YOUR HANDS STILL". Because of the push-pull tubes controls connected to the large control surfaces, if you slide down final approach making your usual small corrections (as you do when landing any spam can), the plane becomes twitchy as it follows your every move.

Once you learn to calm your hands, it is rock solid stable on final, and squeakers are easy.

One heckuva pirep, Jay. I meant to ask you before, did you or Tom do any reconnaissance on this or any of the previous prospect planes on the Van's Air Force website? I would think there would be some information on the build process and challenges there, albeit, a bit cryptic. Any plans to join Van's Air Force?
 
One heckuva pirep, Jay. I meant to ask you before, did you or Tom do any reconnaissance on this or any of the previous prospect planes on the Van's Air Force website? I would think there would be some information on the build process and challenges there, albeit, a bit cryptic. Any plans to join Van's Air Force?

Too late Jay is already a member. :D

Nice write up Jay. Glad it worked out for you so well. Welcome to the world of RV's. :cheers:

Always remember when landing, the nose gear is a kick stand for the prop. Land on the mains only wheelie until you loose the energy to keep the nose up. Protect that gear! :yes:
 
What kind of flying is harder than others on an intermittent electrical problem? How hard was it being flown when it failed the first time?

Tom has spent too many hours chasing THAT possibility. We ALL thought it was a broken wire, at first.

And it may still be. Wires broken inside the insulation aren't unheard of. All we know is that it's intermittent, and has NOT failed now in the last three flights. That's 5 hours of VERY hard flying.
 
Depends, sometimes the shotgun is the economical solution. Not often the case with planes as the parts are some expencive but it does happen

Economical with labor at $75 an hour? Most probably. Adding anything to the collective knowledge of maintenance? Neither a jot nor a tittle.

Jim
 
It's "gates of hell hot" under every cowl. And many voltage regulators are mounted to firewalls.

Which is why all those of us are who are in serious airplane (and other more exotic air/spacecraft) design use parts specified to +150C for the design. If you can't hold your finger on it for two seconds, then it is time for redesign.

Jim
 
Or a broken wire. ;)

If it were broken, it would STAY broken. I disagree at this point in time with Jay's analysis of a thermal problem without a HELL of a lot more test data ... and throwing a new part at it (with perhaps the same thermal problem) will bite them on the butt.

The problem is to FIND the problem and a way to cure it, whether a regulator that can take the heat or a blast tube; the problem is to FIND the problem.

Jim
 
If it were broken, it would STAY broken. I disagree at this point in time with Jay's analysis of a thermal problem without a HELL of a lot more test data ... and throwing a new part at it (with perhaps the same thermal problem) will bite them on the butt.

The problem is to FIND the problem and a way to cure it, whether a regulator that can take the heat or a blast tube; the problem is to FIND the problem.

Jim

Another several hours of flight in brutal heat, with no further alternator trouble. Weird.

I've been run through the ringer, must've sweated out 8 gallons of fluid over the last two days (it's been unusually hot and humid here) but after five hours of intensive training, I'm checked out and signed off.

Look out, world -- that red streak you see coming might be Mary and me! :D
 
It is caused mostly by pilot technique. If you don't come in at warp speed and land flat you won't ever have any trouble with it. With the advent of the power on flat stabilized approach there has been a lot of 172 and 182 nosegear failures from driving them on too fast. Don

The nosegear is a known point of weakness on the RV-8A. One of the mods I had done was to install an aftermarket front axle that (according to Tom, my RV guru) resolves 97% of the problems.

Proper pilot technique takes care of the rest. Land on the mains, keep the weight off the nose, and all is well.
 
If it were broken, it would STAY broken.

Disagree. I can show you a wire right now that has a break of the copper inside the insulation that works about 99% of the time unless it's flexed the wrong direction. (It's in an audio circuit here in the ham shack.)

I need to cut the commercially built switch box and strain relief (didn't do it's job apparently) out of the cable, find the cracked wire, and replace it. Assuming Heil Sound doesn't have a repair program for this particular discontinued product.

As for the rest of your statement, agreed. He hasn't found the actual problem yet... And components rated to 150C... Yep.

I kinda doubt a $27 voltage regulator used those... But they could have. Many automotive rates parts are cheap as heck, compared to certified airplane parts and rated to high temperatures.

My main point was not to go poking new holes through the firewall to "fix" something. There's plenty of voltage regulators that live on the hot side of the firewalls out there, that last for at least a decade.
 
One heckuva pirep, Jay. I meant to ask you before, did you or Tom do any reconnaissance on this or any of the previous prospect planes on the Van's Air Force website? I would think there would be some information on the build process and challenges there, albeit, a bit cryptic. Any plans to join Van's Air Force?

I've read a lot there. Tom wrote the book on RVs, but also recommends that website for ideas and advice. It's a good source of all things RV.
 
The nosegear is a known point of weakness on the RV-8A. One of the mods I had done was to install an aftermarket front axle that (according to Tom, my RV guru) resolves 97% of the problems.

Putting the tailwheel on the back where it belongs solves 100% of the problems.
 
More detail: {...snip...}

Excellent write-up, Jay! You have been bitten! Welcome to the 'dark side'. :D Makes me want to bust out of here early and punch some holes in the sky in the 7A.
 
Putting the tailwheel on the back where it belongs solves 100% of the problems.

Agreed, but mama wanted a nosewheel.

She compromised on tandem seating. I compromised on a nosewheel. It's all good -- and my insurance is half what it would be with the tailwheel version.
 
And, just because I can't get enough of looking at Amelia, here she is in her temporary quarters -- a fully air conditioned hangar, courtesy of a buddy whose plane is up in Dallas for the summer.

1000058_540115152691050_13163677_n.jpg


You can all "oooo" and "ahh", please. It took me a long time to clean her up after two days of thrashing the crap out of it. I could've scraped the bugs off with a trowel! :lol:
 
Last edited:
Back
Top