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How to make a propeller driven aircraft go really fast ?

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Dan Thomas

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I don't think torque is a big problem. We have RC models with enough thrust to hover vertically. The pilot hardly notices torque with a tiny bit of aileron.
WW2 warbirds had problems with it. Some had to limit the initial takeoff power until they had enough airspeed to control the roll.
 

BBerson

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Some had to limit the initial takeoff power until they had enough airspeed to control the roll.
They probably need a bunch of right rudder, but I doubt it's worth going contra-rotation. One Reno racer had contra-rotation, I don't remember if it was worth it. The short blades and hub drag on that look terrible to me.
 

TFF

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Rivets would be cool, but if you update to be the fastest, it would morph into the fastest looking ones today.
 

Speedboat100

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Rivets would be cool, but if you update to be the fastest, it would morph into the fastest looking ones today.

Why ...none of those have a T-tail...nor a swept wing ?

Rivets had a post was era wing foil.
 

Steve C

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One Reno racer had contra-rotation
There have been 3. Red Baron, Precious Metal and Miss Ashley II.

I read about Critical Mass having trouble as originally built where it didn't have enough rudder to use full power on takeoff. Somebody designed a new fin/rudder and it solved the problem.
Roll control is not generally a problem. Rare Bear has tiny ailerons.
 

mcrae0104

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I looked up Precious Metal record on wiki and didn't see any gold wins.
You're right. I don't think it achieved its full potential before it was destroyed in a fire.
1601753788243.png
 

Speedboat100

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I think the counterrotating prop comes to play when you no longer can extend the pro size and their amount.
 

Speedboat100

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rv6ejguy

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robust

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Pedalling has taken man at 144 km/h ( 89 mph ) and solar power high nearly 300 km/h....and put them together and you get 144+300= 444.
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Your arithmetic is not correct. You can't add it like that. Drag is proportional to the square of the speed.
 

Speedboat100

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I agree you cannot....or you can, but it does not hold water.

Pedalling would bring around 2-5% more power to a light system and solar power 10% of the needed energy to fly efficiently.....or rather practically.

You still need the 85% from the batteries ( or other system ).

If you fly solar and pedal power alone you are restricted to speeds of 30-50 km/h ( faster at high 80-100 km/h even ).
 
Last edited:

poormansairforce

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I agree you cannot....or you can, but it does not hold water.

Pedalling would bring around 2-5% more power to a light system and solar power 10% of the needed energy to fly efficiently.....or rather practically.

You still need the 85% from the batteries ( or other system ).

If you fly solar and pedal power alone you are restricted to speeds of 30-50 km/h ( faster at high 80-100 km/h even ).
How did you manage to get soooo far off topic on your own thread???
 
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