Spit IIa Performance graph

[Crumpp]

Be carrefull with overboost at high altitudes

Which is realistic. At high density altitude, you will see a performance decrease at high boost and rpm. What happens is the prop tip speeds become excessive and you lose efficiency. So instead of increasing thrust, you actually reduce the thrust the propeller is able to produce.

In otherwords, at standard conditions and low density altitude you have the chance of realizing a performance increase at high boost and rpm.

You can also see by your test that the 2800 rpm data is almost an exact match looking at SL and your test FTH on a standard day. Your recorded FTH is off though for a standard day.

However, the FTH does not match 29.29inHg at 66.2F.

What are the temperature and pressure you recorded the data under?

I am not sharp shooting your effort. Trying to help you guys get the data you want to make sure all the FM's are correct. If you don't give the developers the information they need, then they cannot find the issue and fix it.

Some details that need to be included in each test:

Take off weight

There is a control somewhere to set the temperature and pressure. If you can set them too:

SL Temperature 15C
SL pressure 1013.25mb

Climb speeds

Engine settings and rpm

FTH

You have a well organized set of data that is easy to work with combined with visual graphs to spot trends. That is great.

Don't forget too that the details of the RL performance are extremely important as well. How the aircraft is set up, weight, configuration, etc...

All of these effect performance.

Lastly, aircraft performance is a percentage range so looking at a single set of data from a real aircraft may not be representative of the typical performance of the type.

For example, the Spitfire test P7280 does not seem to have a rear view mirror listed.

This aeroplane was fitted with a bullet-proof windscreen, armour plating over the petrol tank and externally, apart from the radiator, was similar to the Rotol Spitfire I, N.3171, previously tested at this establishment.

http://www.spitfireperformance.com/spitfire-II.html

The absence of a rearview will effect the Vmax of the airplane in the Spitfire. The presence of the mirror is noted in RAE test's.

Aircraft performance is all about the specific conditions!