Sharing some info and pictures of my tethered hydroplanes

[longballlumber]

very cool! thanks for sharing!

 

[Grimracer]

WOW.. I am not of the opinion.. we RCers have little idea what we are doing...LOL.. kidding.. very good stuff!

Grim

 

[Grimracer]

is there "electric" tether racing?

Grim

 

[Ricky Neal]

is there "electric" tether racing?

Grim

Indeed there is, AE and B1E are the more common classes for electric. B1E models are very similar to the B1 class models and the AE models are similar in dimension to the A1 .21 class. See the International records below:

AE - 42v limit - 1.2kg - 1456.31 mph
B1E - 42v limit - 0.75kg - 169.87 mph

 

[Terry Keeley]

Very cool!

We tend to think in lbs. and ounces over here so I converted your 228g to about 8 oz (1/2 lb.) and 800g is about 1 lb. 12 oz.

Very light!

If you stick to it I think you will like the results you can get with CF...

 

[ALLAN YUEN]

Indeed there is, AE and B1E are the more common classes for electric. B1E models are very similar to the B1 class models and the AE models are similar in dimension to the A1 .21 class. See the International records below:

AE - 42v limit - 1.2kg - 1456.31 mph
B1E - 42v limit - 0.75kg - 169.87 mph

How work ? Run to stop use radio? Or timer for shut power off ?

 

[Ricky Neal]

How work ? Run to stop use radio? Or timer for shut power off ?

A radio is used but it has to be hands-off for the timed run. - Also, I meant 146.31 mph, not 1456.31 mph (that would be impressive!)

 

[gooycheese]

Yeah lol.... 1456 would be far more than impressive... Almost double the speed of sound would be insane.

Awesome hobby... Thanks for the info and pictures... More pics and videos would be awesome.

Thank You

 

[RaceMechaniX]

Thanks for posting Ricky. What's the theory of mounting the aero engines horizontal versus vertical position like the boats and cars?
Is the speed an average over the timed laps or just the maximum for one lap during the timed laps?

Keep the details coming.

 

[Mike Hughes]

Looking at your tank pics, you guys are running a pito for tank pressure? No pipe pressure?
Mike

 

[francois peilleron]

do you have noise limit,one of your pipe seems to have a mufler;so far the tether car do not have db limit

 

[Ken Retallick]

Hi Ricky,

Very impressive! I have seen tether cars in action, Fastest was A class with a picco similar to yours over 320Kph. I think the record is well over 340 now. The speeds you achieve on water would be awesome to see for real!
Alot of similarities with the cars.

 

[Ricky Neal]

Thanks for posting Ricky. What's the theory of mounting the aero engines horizontal versus vertical position like the boats and cars?
Is the speed an average over the timed laps or just the maximum for one lap during the timed laps?

Keep the details coming.

Not all B1’shave the engine on their side, this is built this way as it fits better on to the F2A speed pan better. Just better packaging really.

The video i posted above shows this model in a lot more detail and you see just how tight everything is.

The speed is calculated as an average of 8 timed laps. Its down to the operator to give the signal for when to start counting.

This enables the boat to build up speed but you have to be carful, if you start counting too soon you don't get full advantage of the fastest average speed, too late and the engines can overheat and slow down or even run out of fuel as they only really carry just enough to keep weight down

 

[Ricky Neal]

Looking at your tank pics, you guys are running a pito for tank pressure? No pipe pressure?
Mike

Hi Mike,

Im not sure that i would describe it as a pito tube tank as such but its along those lines.

We run no pressure at all but the tank has a vent at the front and once upto speed the centrifugal forces pushes fuel into the pick up. We actually partially tune the engine with the tank position.

I will try to post some pictures of the tanks and how they are plumbed because its quite unique as far as I know and difficult to get right

 

[Ricky Neal]

do you have noise limit,one of your pipe seems to have a mufler;so far the tether car do not have db limit

In the UK we are governed by the MPBA and we have to abide by their noise limits. Its a pain in the ass to be honest as it really does restrict performance to a degree.

At international events we so far are ok to run open pipes.

In my opinion its a bit harsh as we only ever run for a couple of minutes at a time and we only run one boat at a time but rules are rules i guess

 

[Ricky Neal]

Hi Ricky,

Very impressive! I have seen tether cars in action, Fastest was A class with a picco similar to yours over 320Kph. I think the record is well over 340 now. The speeds you achieve on water would be awesome to see for real!
Alot of similarities with the cars.

We run slower boats (100mph limit) in a public park in London and it always draws a crowd and this is with the small 3.5cc boats. Its very impressive, especially the bigger boats

We are quite a but behind the tether cars in terms of speed but the added dimension of water makes it more difficult and props make a huge difference as well.

Im tempted to start running cars as well as its just seems a little easier but we do not have a track in the UK where we can run competitive cars. Only slower and vintage stuff. I believe they are looking at getting that track ready for the faster stuff though so i may have a go of that as well

 

[Mike Hughes]

Hi Mike,

Im not sure that i would describe it as a pito tube tank as such but its along those lines.

We run no pressure at all but the tank has a vent at the front and once upto speed the centrifugal forces pushes fuel into the pick up. We actually partially tune the engine with the tank position.

I will try to post some pictures of the tanks and how they are plumbed because its quite unique as far as I know and difficult to get right

A pito tube refers to an air pick up on a wing of airplane for speedo. You have the vent tube facing forward in the direction of air. I was wondering if that play a roll in the tank pressure.

 

[Wasted wages]

Ricky,
Do you run mono hulls as well or is this strictly a hydro type thing ? any outboard classes ?
I think some of the steam powered engines would be cool to see a video of..

Being as the boats are more airplane than boat, it would appear that centrifugal force would play a huge part in the ultimate design keeping the prop planted in the water.
Is the bridle adjustable front to rear to account for any prop walk? or AoA ?

I know you said the club has different sized cable for different classes, but has there been any progress of using difference type of materials ( kevlar, polys, carbon fiber ) to cut down on air drag and weight ?

Also, on the center pole, is there a specialized bearing that the cable rides on ? again looking at drag etc...even as tiny as this might be, it could be the difference in setting a new record.

Thanks for sharing!! this is an interesting view into a part of our hobby not seen in the states !!
Keep it coming!

 

[Charles Perdue]

I understand that recently the wire size used for the 60 size tether cars at the track in California had to increase the size of the wire due to the increasing speeds.
Insurance purposes I suppose.

Charles

 

[Ricky Neal]

A pito tube refers to an air pick up on a wing of airplane for speedo. You have the vent tube facing forward in the direction of air. I was wondering if that play a roll in the tank pressure.

I am not sure to be honest, it could have an effect I am sure but I look at it more as letting air in to prevent a vacuum. The main force for fuel feed seems to be the centrifugal force but I will post some pictures later of how the tanks are constructed and it may provide more info that I can.