Twin Jet Ultralight

[Admin]

Now this is my kinda plane:

 

 

 

[fly_tornado]

A small plane with a big plane sound.

 

 

[dazza 38]

Looks great but shes noisy.That would upset the greens.:peepwall:

 

 

[dunlopdangler]

Looks great but shes noisy.That would upset the greens.:peepwall:

no more noisy than bob browns whining..

 

 

[Guest SAJabiruflyer]

Dont bring it to Hindmarsh Island :peepwall:

 

 

[Guest Maj Millard]

Looks like it could use four by that take-off run, but I still seriously want one !! The potential with those engines is unlimited. Will this be what we are flying in ten years ???...............................................Maj...

 

 

[Admin]

Not only could you put twin time in your log book but also jet time...at say $100 - $150 and hour...that would be an impressive log book for a recreational aviator even though it would need ga reg, still recreational

 

 

[dazza 38]

I wonder what the fuel burn for the twin jets would be ? I wouldnt know where to start looking.Anybody got a ball park figure?

 

 

[Kyle Communications]

The fuel consumption for model jet turbines is pretty horrendous. 16kg thrust engines consume around 600ml per minute of avtur at full power...the engines he had on that looked like Jetcat 200 they produce 20kg of thrust and consume around 1 litre per minute EACH.....your going to need a lot of fuel...also the maintenance is every 25hrs usually a set of bearings thats about 300 bucks each engine then also a balance is needed as well because as soon as the engine comes apart it needs to be balanced. I have one of only a couple of the balancers that can do the job. I bought it to service the model turbines I bring in. We also service and repair all other brands including jetcats. The balancer I have balances to as low as .02 gramms per millimeter....that is extremely low and is required for these turbines as the rpm is so high. The engines he has will be doing around 108,000 at full power and idle around 30,000....the smaller the turbine the faster they go one of my small turbines it puts out 4kg of thrust it idles at 90,000 and full power is 190,000 there is even a smaller one now that puts out 1.5 kg of thrust and idles at 120,000 and full power is 240,000

 

Mark

 

 

[Admin]

I shall reconsider my cost per hour to have an interesting log book

 

 

[dazza 38]

Thank you Kyle, it is not sounding real practical now with the information you have provided.120 litres per hour running both jets, it is starting to sound expensive.Then have to be content with the 25 hour overhaul.

 

 

[facthunter]

The problem of fuel efficiency of small jet engines will preclude them being a serious contender for practical flight, forever, as far as I can see, Many things in aeronautics don't scale down well. This is one place where "bigger' is better. The fuel usage improvement in larger jet engines has been the main factor in reducing the operating cost and increasing the range of the modern Jet Airliner.

 

IF smaller engines could be done the cost would not be justified with the limlited volume, and value of the market. The developmental costs of large jet engines has nearly bankrupted large companies and governments too, in the past. Scary business investing in it, for anybody... Nev

 

 

[facthunter]

Another annoying thing about "pure" ( non-bypass) jet engines is the low thrust comared with coupled (turbo prop) or Bypass (turbo fan) multi spool engines. This gives poor take-off performance, ( evident in he Video). and would give poor climb performance too .

 

Jet engines do not suit low speed, or low altitude applications either. A jet engine can maintain a constant thrust so the faster it goes the more equivalent horsepower it makes, for the same fuel flow. Nev

 

 

[Kyle Communications]

There are guys out there developing turbofans and a few are quite successful. Using much smaller turbines they are getting high thrust levels. But these are difficult to make with the concentric drive shafts. There have been a couple of multistage model turbines made but are very expensive and very finicky....As time goes on they will get better. I imported my first turbine in 1999 it had 23lb of thrust....in the mainstream the only thing that has changed is kero start instead of gas...although I must prefer the gas start less chance of fuel fires and the turbines are getting cheaper. Kingtech supply a 16kg thrust engine its made in Taiwan they manufacture aerospace stuff and full-size turbine parts the engine is about $3000 that is really cheap most others are around $5000 each

 

 

 

[Gnarly Gnu]

Fantastic! Tempted to take a digital recording and replay over a loudspeaker during flight. Maybe next time I go by the Goolwa area....