British FM killing the fun of the game for allied pilots.

[Crumpp]

It's interesting that all tested aircraft displayed longitudinal dynamic instability.

Where does this come from??



It is patently false as a generalization.

While many WWII fighters were unstable in very specific conditions such as in climb power with a specific speed range or landing configuration.... most were stable and met the requirements.

It is was very rare for a design to be unacceptable over the range of the envelope such as the Spitfire.

[bongodriver]

Originally Posted by Crumpp

Where does this come from??



It is patently false as a generalization.

While many WWII fighters were unstable in very specific conditions such as in climb power with a specific speed range or landing configuration.... most were stable and met the requirements.

It is was very rare for a design to be unacceptable over the range of the envelope such as the Spitfire.

Read page 18 of the NACA report and note the conclusion of satisfactory for short period oscilations (remember they were the ones that really counted)
and was noted as satisfactory for stick force gradient appart from 'flaps down power on', page 19 is good reading too.
Then try to show your smug face here again when you realise you have been completely discredited.

http://jsbsim.sourceforge.net/spit_flying.pdf a link to the report

[JtD]

....most were stable and met the requirements.

Which requirements were there for long period dynamic longitudinal stability?

[bongodriver]

Originally Posted by JtD

Which requirements were there for long period dynamic longitudinal stability?

And this is the million dollar question, even Crumpps NACA 'bible' states that long period stability was not looked in to much as it is of no particular consequence....so it seems the much maligned Spitfire failed 'slightly' in a characteristic of little to no significance, in summary it can be asumed they used a basic rule of stability is beter than instability in this regard so they gave the Spit an 'F' and Crumpp something to cling to.

[winny]

Originally Posted by JtD

Which requirements were there for long period dynamic longitudinal stability?

The requirements are set out in NACA Report No.755. By R. R. Gilruth

I posted a link to it a couple of pages back.

EDIT:http://aerade.cranfield.ac.uk/ara/19...report-755.pdf

[JtD]

Originally Posted by winny

The requirements are set out in NACA Report No.755. By R. R. Gilruth

There's nothing about long period dynamic longitudinal stability in there, hence my question.

[swift]

Would you mind to continue the stability discussion in this thread:

http://forum.1cpublishing.eu/showthr...=33245&page=94


so we could continue discussing the general performance of the spit in the recent patch that is speed, overheating and climb?

Some people are interested in these issues.

[NZtyphoon]

Originally Posted by swift

Would you mind to continue the stability discussion in this thread:

http://forum.1cpublishing.eu/showthr...=33245&page=94


so we could continue discussing the general performance of the spit in the recent patch that is speed, overheating and climb?

Some people are interested in these issues.

Too true, Crumpp can continue with his Spitfire elevator fetish on his own time - his bug tracker has gotten nowhere and he just wants to re-litigate this non-issue by hijacking this thread.

Has anyone got the engine data in the Spitfire I and Hurricane I Pilot's Notes?

[TomcatViP]

Originally Posted by NZtyphoon

Too true, Crumpp can continue with his Spitfire elevator fetish on his own time - his bug tracker has gotten nowhere and he just wants to re-litigate this non-issue by hijacking this thread.

Has anyone got the engine data in the Spitfire I and Hurricane I Pilot's Notes?

If you hdn't buried his point of view with your wall of text and insulting comments we might hve hd the opportunity to raise some interesting point. Do you know tht or are you tht much overdone?

[Crumpp]

Which requirements were there for long period dynamic longitudinal stability?

The requirements for long period oscillation in highly maneuverable aircraft is the slope of the velocity change should not exceed .04 difference.

Do you need me to calculate it or can you compare the slope of a line on your own?

Transport catagory aircraft have a less restrictive stability requirement which require a period of 55 seconds.