2011-02-16

Power to weight ratio in comparison

Insert from my comment in HBA ( homebuiltairplanes.com ):

Here is DA-100 2,5 kilos each..together 5 kilos; Desert Aircraft

Output is 20 hp ( 9,8 + 9,8 = 19,6 exactly ).

5+47 is 52 kilos..props, mounting..more wheels etc...and 60 kilos is reached quickly compared to Minibat.

It won't be really unlimited in aerobatics but similar to weak powered trainers.

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FAF Valmet Vinka trainer has 200 hp engine and max flyweight is 1250 kg. This gives power to weight ratio 0,16 hp/kg or normally loaded 0,18 hp/kg.

Valmet L-70 Vinka - Wikipedia, the free encyclopedia

My design FNX II with 2 x 9,8 hp engines and typical 80 kilo pilot and 5 kg fuel would indicate 0,135 hp/kg.

So conclusion; the cheapest and weakest engines would make it moderatly aerobatic and slightly more powerful DA-150 would add 3 kilo in engine weight, but yield power to weight ratio of 0,22 hp/kg ( this is WW II fighter niveau ) ! At least in par with T-6 Texan/Harward; http://en.wikipedia.org/wiki/T-6_Texan and fighters of the -30ies like Hart; http://en.wikipedia.org/wiki/Hawker_Hart

Desert Aircraft

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Not even ZDZ210 J won't take it to the Spitfire MK 1 power to weight ratio; http://www.troybuiltmodels.com/items...V-JENGINE.html

0,293 hp/kg OTOH is pretty close to some weaker fighter designs.

http://www.troybuiltmodels.com/items...V-JENGINE.html

This engine has also electric starter option; http://www.zdz-modelmotor.cz/UserFil...%20ENG2010.pdf

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Had to look for many WW II fighters to find 0,33 hp/kg and found one; http://fi.wikipedia.org/wiki/Morane-Saulnier_M.S.406

60 kilo pilot with 2 x ZDZ210 J would have same p / w ratio !!!


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Compared to aerobatic Fournier F4; http://www.cfiamerica.com/id4.html

Even the 9,8 hp engines are powerful since the Fournier power to weight ratio for aerobatics is 0,11 hp/kg and for cruise 0,1 hp/kg.



Unfortunately the links got corrupted.

2 comments:

  1. Intereting, when is your plane planned to fly

    ReplyDelete
  2. I am busy at work and sorta outmanned at workforce for the project...also no orders.

    Model could fly next summer.

    I have some remorse too.

    ReplyDelete