How to calculate top speed of an aircraft
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Surely when a large aircraft manufacturer works out premeditated and forecast performance they use more than just mathematical equations?
I am far from an expert on this so on my part its guesswork but they have access to wind tunnels where they can test and modify structures which make up the aircraft?
Take winglets which may be used on a progressive design?
they will be designed, tested and modified to create an effect?
They will be tested alone in the wind tunnel with sensitive instruments measuring everything from pressure to airflow and then tested with the wing?
That data will then be used to workout performance gains.
I am sure its not a case of sitting down with a blank sheet and saying x+y-z=127.7 KTS
Pace
I am far from an expert on this so on my part its guesswork but they have access to wind tunnels where they can test and modify structures which make up the aircraft?
Take winglets which may be used on a progressive design?
they will be designed, tested and modified to create an effect?
They will be tested alone in the wind tunnel with sensitive instruments measuring everything from pressure to airflow and then tested with the wing?
That data will then be used to workout performance gains.
I am sure its not a case of sitting down with a blank sheet and saying x+y-z=127.7 KTS
Pace
Join Date: Aug 2006
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Aircraft performance estimates.
As well as all the textbooks listed. The John Roncz spreadsheets are a great tool for a first look.
https://www.google.co.uk/url?sa=t&rc...lH978_OpjG2vCg
I hope this helps.
Charlie
https://www.google.co.uk/url?sa=t&rc...lH978_OpjG2vCg
I hope this helps.
Charlie
Surely when a large aircraft manufacturer works out premeditated and forecast performance they use more than just mathematical equations?
I am far from an expert on this so on my part its guesswork but they have access to wind tunnels where they can test and modify structures which make up the aircraft?
I am far from an expert on this so on my part its guesswork but they have access to wind tunnels where they can test and modify structures which make up the aircraft?
The results would then be checked by hand calculation by reference to historical data sheets - such as ESDU.
Then sample critical aircraft structure would be built and tested to destruction, and representative models would be put in the wind tunnel, matched as far as possible to Reynolds number, then scaled to the complete aircraft.
Then it's flight tested, to validate the aerodynamic estimates.
Take winglets which may be used on a progressive design?
they will be designed, tested and modified to create an effect?
They will be tested alone in the wind tunnel with sensitive instruments measuring everything from pressure to airflow and then tested with the wing?
they will be designed, tested and modified to create an effect?
They will be tested alone in the wind tunnel with sensitive instruments measuring everything from pressure to airflow and then tested with the wing?
The main instrumentation will be forces and moments - but it's common to pressure tap sections of lifting surface to generate pressure distributions. When I worked in the tunnel on what is now Typhoon, we also had moveable control surfaces, and re-tested at lots of control settings, AoA values, and even some Beta variations.
Flow visualisation isn't used that much, but has value in identifying interference drag issues, and boundary layer thicknesses for instrument positioning particularly.
That data will then be used to workout performance gains.
I am sure its not a case of sitting down with a blank sheet and saying x+y-z=127.7 KTS
I am sure its not a case of sitting down with a blank sheet and saying x+y-z=127.7 KTS
And even then, they're not as trustworthy as flight test data - and there will be differences.
G