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RV-7 on Amphib Floats Flying

Cool !!!

Great clips and wonderful news. I really enjoyed talking with the late Eustace Bowhay about his RV on floats. Sure miss him.

I'm really glad another RV is now 'on the water' and am looking forward to seeing it at OSH. Thanks again for posting the links to the videos. I'm also looking forward to more pics and descriptions on Wally's web site.

Best,
Doug
 
Doug: How about an Interview?

Hey Doug: How about getting an interview with Trey and posting it on your website? It would be interesting to hear about his experiences with installing the floats and how his airplane performs, etc.
 
In the works

As part of the professional video (as opposed to my ham fisted efforts) Trey was interviewed when he returned from the test flights. This should be on Synergy's site in the near future.
 
That is soooo cool!

Great job!

One question and this is not a flame of any kind.

Why use a -7 and not the -9? I would think that the 9's longer, high lift wing, would be the better choice. More so since you can't do acro.

Was the -7 selected because of the 180 to 200 hp option?

Makes me wonder how a 160 HP -9 would work. Better yet, a 135 hp O-290 powered -9. ;)
 
Maybe the G-limits of the airframe seemed more attractive? I mean a seaplane needs more power, so the 200HP is nice. On the other hand, the -9 is the same fuse, so planning on putting a 180HP on amphib -9 might work fine. Other than that, I can't see a reason the -9 wouldn't work great.
 
7 vs 9

Part of the thinking was indeed the beefier structure of the 7. The motor is an Aerosport IO390 & even though this wasn't decided until after the emp was completed Trey is experienced enough in float plane ops to realise that 160 HP was not going to deliver the performance he required.
 
No bash at all, just a question for the non-float plane types like myself. I personally think this is way cool, but I have to ask anyways.... Isn't a low wing airplane a rather terrible candidate for floats in general? I just have visions of jumping out on the back of the float and then needing in front and jumping over the wing and then needing back up on the wing again and so on. I guess everything is a trade off and perhaps the beefiness of Van's planes in general plus some of the performance over "standard" float type airplanes is enough to outweigh the downfalls. Anyways just curious....

Scott
RV-9A - N598SD Flying
 
RV_7A said:
Theres the long sought after solution to the "A" nose wheel collapse issue!!!!! -Jeff
Click to expand...

And if you look at the second photo on the VAF main site, he appears to be landing with a stopped prop, and the wheels down.

That wheel sticking out sure doesnt look like it will slice through the water very well.

Mike
 
RV_7A said:
Theres the long sought after solution to the "A" nose wheel collapse issue!!!!! -Jeff
Click to expand...

And if you look at the second photo on the VAF main site, he appears to be landing with a stopped prop, and the wheels are down.

That wheel sticking out sure doesnt look like it will slice through the water very well.

Mike
 
Mike S said:
And if you look at the second photo on the VAF main site, he appears to be landing with a stopped prop, and the wheels are down.

That wheel sticking out sure doesnt look like it will slice through the water very well.

Mike
Click to expand...


In the video you will see that the wheels extend down even more for land ops. Notice the gear arm extending out that the wheel is attached to. In the photo referenced the wheel is retracted as far as it goes. Look at other amphib floats and you will see the wheel is exposed. The floats should ride high enough to keep the exposed wheel from being an issue.
 
Mark, thanks----------I am used to seeing float setups where the wheel swings back and up, tucking into the front of the float.

This is a new configuration for me.

Mike
 
No, Jeff

RV_7A said:
Theres the long sought after solution to the "A" nose wheel collapse issue!!!!!

-Jeff
Click to expand...
This is not an -A, it would be the solution for ground-loops. :eek:

Kent

I wonder how long it takes to remove the floats and put the wheels back on.
Very cool, I want more information about this plane.

Kent
 
Be careful Bill,

N941WR said:
Makes me wonder how a 160 HP -9 would work. Better yet, a 135 hp O-290 powered -9. ;)
Click to expand...

You are so... close now, don't what to be adding new options now. :p

Kent
 
So Steve my old colonial buddy!

Was the red camera ship the one you were buzzing my house with?

So nice of you to fly round and round on a beautiful day while I was sweating buckets replacing the roof on our rental!

Mind you the sweat equity pays for aerobatic school in 3 weeks time so its not all bad...:)

Cheers

Frank
 
N941WR said:
Great job!

Why use a -7 and not the -9? I would think that the 9's longer, high lift wing, would be the better choice. More so since you can't do acro...
Click to expand...

Acro with floats! Now that would be cool.
 
wow!

First... Fantastic.

Second.... Is it insurable? :confused:

Third... Shall it be called the RV-7W? or RV-7B? :rolleyes:

Best Regards,
Jeff Caplins
RV-7 (1 more year before continuing the building process)
 
An end to the primer wars?

At last, a good reason to prime your RV! Or at least, a good reason to question my decision not to!
 
jcaplins said:
Third... Shall it be called the RV-7W? or RV-7B? :rolleyes:

Best Regards,
Jeff Caplins
RV-7 (1 more year before continuing the building process)
Click to expand...

Maybe RV-7F (Floats) or RV-7S (Seaplane)! :rolleyes:
 
Gross Weight???

Anybody have any details on what was done to beef up the structure? I noticed at Arlington that the empty weight was something like ~1527# and the gross was listed at ~2300-2400#.

Is there any additional structure to justify the huge increase in gross weight? If so, any details?
 
alpinelakespilot2000 said:
Anybody have any details on what was done to beef up the structure? I noticed at Arlington that the empty weight was something like ~1527# and the gross was listed at ~2300-2400#.

Is there any additional structure to justify the huge increase in gross weight? If so, any details?
Click to expand...

I *think* I remember that with float planes the weight of the floats is typically added to the original gross weight of the aircraft. Thus the gross weight of a float plane is typically MUCH higher than that of the same plane on wheels. The empty weight goes up and the gross weight goes up...so the useful load remains about the same. The justification for this is that the floats provide considerable lift while the airplane is flying. Outside of the float attachment apparatus no structural beefing up is typically warranted in this setting...I think.

Please somebody with experience correct me if I'm wrong here.

Dan
Chicago
RV-9A empennage
 
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increase in gross

I have been flying various float planes in alaska for almost forty years and in some cases the gross is increased when on floats and in some it has not. the majority of the time the gross remains the same and in no case that i am aware of does the gross increase by the weight of the float installation. Gross weight is limited by a number of factors for each airplane. In some cases the fusalage of a plane is strengthened when on floats because there are four supports for landing and torsional forces are reduced. and while it is true that floats in many cases do provide some lift i can not believe that they lift their own weight. Some floatplanes such as most all Cessnas retain the same gross, while super cubs get a small increase in gross when on floats. In all cases there is a distinct loss in all performance criteria. Usefull load is down, cruise speed is down, takeoff distance is way up and rate of climb is way down. and if you put the plane on amphib floats the loss is even greater. Of course when you are going to a remote lake with no roads one can be forgiving of the reductions in performance. After all there are very few wheel planes that can land and takeoff from water. Having said this I would love to be able to put my 180HP 9A on straight floats and would appreciate any tech data for such an installation. I think that it would be the best of the RVs to put on floats because of its lower stall speeds. Low wing float planes are not common and do present docking problems not associated with high wings. Piper cherokees beech 18's bamboo bombers, astecs, just to name a few have been put on floats. the lake amphib on the water presents even greater challenges. However with the 9 it looks like one could go off the front or back of the wing when beeching or docking without too much problem provided that the prop was not turning. The 2200 aeroset floats would be a perfect match as would the EDO 2000's and would not add too much weight after removal of the landing gear. What a bomb it would be. high cruise, good takeoff and climb, ecomomical, and still with a decent payload. I really would like to do this. can anybody help?
 
VNE

Just a though from a land lubber- there is little water to land on in OZ.

Do floats have their 'OWN" VNE.
Can you simply put, for example, Cub floats on a Harmon Rocket and roar around at CRZ speed?

Pete.
 
Increase in gross weight ...

With type certificated aircraft, as noted above, some aircraft get a gross weight increase when on floats, and some don't. It all depends on what exactly was the reason why the gross weight is where it is for the land plane. If the gross weight is there for structural reasons, then it probably can't be increased when floats are installed (unless it is the landing gear structure that is limiting the gross weight).

But, on some aircraft, the gross weight is selected so the aircraft just meets the climb performance requirements. For some strange reason, the required climb performance in FAR 23 is lower for aircraft that are on floats. The required climb gradient at sea level, std day is 8.3% for land planes, and 6.7% for float planes. So, for these aircraft, the allowable gross weight may be higher when on floats than it is without floats, as even with the increased drag of the floats, the aircraft can probably do better than 6.7% climb gradient at the land plane gross weight.
 
RV on floats

Can anybody provide a way of contacting Trey Johnson who was in Eugene Or? i have a 180 RV 9A that I would very much like to put on floats. thanks.
 
What make/model and how much$

questair said:
The 2200 aeroset floats would be a perfect match as would the EDO 2000's and would not add too much weight after removal of the landing gear.
Click to expand...
The *Aerocet 2200 are straight floats only (no gear) and they cost $17,000 (w/ no hardware). Not too bad. They displace 2230 lbs. fresh water. Straight floats make sense (cost & weight) especially if you live on a lake.


What kind of amphibian floats did this Gent use on his RV-7? I am no expert, I am asking? They could be wipaire, model 2100? They only cost $32,000 (minus hardware, rigging, hydraulics, gear advisory) and displace about 2200 lbs and weigh 410 lbs. Figure another $8,000 to $12,000 grand so $40k for amphib floats.

http://www.wipaire.com/products.html

I have seen float planes and that RV-7 looks good getting on and off the water. Float planes do flip and sink so you better have a way to get out quick upside down in the water.


A friend, retired airline pilot has a C180 on amphib floats. The first time flying with him, doing a touch and go (splash and go) on a lake was freaky. Jet-skis and sailboats nearby, the feeling as we got closer to the water and touched down was odd. You know its cool but your mind is saying BAD THING! :eek:

*Pirkka, typo corrected, you are too quick, thanks :D
 
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amphibs vs straight floats

i have had several amphib and straight float planes and can tell you that amhibs are a big compromise. And most important is while you can stand a runway landing with the gear up, you can not stand a gear down landing on the water. so the advisory gear system is a must. The weight ofr an amphib installation adds at least a third more weight and in some installations equals another person that can not be taken, not to mention the first person just because of a straight float penalty. In my 185 with EDO 3500 amphibs, my useful went to 860#, down from over 1300# on wheels. I feel that the penalty on a RV would be just too much with Amphibs, but could easily be tolerated with the 2200 Aerocets. I just need to know how to get this accomplished on my 9A. Any ideas?
 
RV7 on floats

Send me an email & I will pass it on to Trey. Just to confirm the floats are made by Claymar. Trey has also had a 185 on floats.
 
In April AOPA Pilot

In the April 2008 AOPA Pilot, Mark Twombly's "Pilotage" column is about getting a ride in Trey Johnson's floated RV-7. Sounds like he had fun.

Looking at those Youtube videos, though, the aircraft seems to have a tendency to porpoise when landing on water. Anybody else flown it, and can comment?
 
Eustace Bowhay

I'm wondering if anyone know's what happened to Eustace' Bowhay's float plane? Is someone flying it up here in Canada?
 
lift from floats???

djvdb63 said:
The empty weight goes up and the gross weight goes up...so the useful load remains about the same. The justification for this is that the floats provide considerable lift while the airplane is flying.

Please somebody with experience correct me if I'm wrong here.
Click to expand...

Maybe this is something for mythbusters but for now, THINK ABOUT IT... Floats are flat on the top and generally curved on the bottom. If there is lift, it would be negative lift. Also, I'm pretty sure that floats are generally installed with a slight negative angle of attack, not sure how much. This would mean huge negative lift and drag during cruise and less so in climb when at high angles of attack (for the wing).

If there are increases in gross weight is would be partly because of how the aircraft will be used. Ie: it won't be very aerobatic. It will be flown very carefully. It's now a truck and there are no conventional landing gear to be overloaded. Gross weight will also be increased because it has to for the A/C to be useful and therefore climb and speed would be compromised.

Power is often increased when on floats because of increased drag and less fear of operating too close to VNE.

I asked Van once about putting a 7 on floats. He only said, the 9 would be better in his opinion.

My opinions. Anyone may correct me if I'm wrong here.

Bevan
RV7A on wheels (for now)
 
Does anyone know about the performance of this plane

I have never seen any number. How fast is it? What is the fuel consumption? What is the max alt?

Kent
 
I am not so sure about the float airfoil

Bevan said:
Maybe this is something for mythbusters but for now, THINK ABOUT IT... Floats are flat on the top and generally curved on the bottom. If there is lift, it would be negative lift. Also, I'm pretty sure that floats are generally installed with a slight negative angle of attack, not sure how much. This would mean huge negative lift and drag during cruise and less so in climb when at high angles of attack (for the wing).

Bevan
RV7A on wheels (for now)
Click to expand...

I think that the step on the bottom of the float would spoil any negative lift.
You may be right on the rest of it. I would sure like to get more information from the builder.

Kent
 
My RV-9, N942P put on Baumann 2100 straight floats two days ago. Test flights are positive and just minor adjustments needed. With 180 HP acceleration is very good, plane gets on the step right now and lift off comes quickly. Cyl temps around 400 on hottest cyl at warm OATs. Seeing 150MPH at 2300X 23"all with a 72" blended airfoil. Have ordered a 210 MT two blade CS ( 83") which will take a few pounds off the nose and which should provide considerably better performance.
 
kentb said:
I think that the step on the bottom of the float would spoil any negative lift.
You may be right on the rest of it. I would sure like to get more information from the builder.

Kent
Click to expand...

I'm pretty sure that when the designer is installing floats, the "angle of incidence" of the floats (for lack of the proper term...) is selected to produce the minimum drag in cruise flight while still keeping the wings at the proper angle of incidence to be able to rotate and fly off the water. If the floats are at "zero angle of attack" in level, cruise flight, then they are most likely at some positive angle of attack (ie, producting lift) when maneuvering (ie, pulling g's).

Or not.....I could be way off!

Either way, COOL concept! I, too, think the RV9 with a 200 hp and a CSP would be an awesome float plane! Somebody here should DO IT!

CDE
 
questair said:
My RV-9, N942P put on Baumann 2100 straight floats two days ago. Test flights are positive and just minor adjustments needed. With 180 HP acceleration is very good, plane gets on the step right now and lift off comes quickly. Cyl temps around 400 on hottest cyl at warm OATs. Seeing 150MPH at 2300X 23"all with a 72" blended airfoil. Have ordered a 210 MT two blade CS ( 83") which will take a few pounds off the nose and which should provide considerably better performance.
Click to expand...

Pictures? Very cool. Love to hear more about this.
 
I know how much everyone loves their RV's but the utility of a low wing aircraft on floats seems really limited. A high wing design offers so many large advantages it just seems that might be a better way to go.
On the flip side however that is what is great about experimental aircraft. You can do anything you want!

George
 
You are correct about utility of a high wing vs a low wing. Easier loading, ability to walk under the wing, no rain in the cockpit, easier docking and river bank operations. But the disadvantages are just inconvenient and require a bit more planning. The nearly 150MPH speed at 8 1/2 gph offsets a lot of the inconvenience however.
 
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