Flight Testing in CoD

[TUCKIE_JG52]

Originally Posted by kimosabi

There's no use going by FM testing as detailed as this one yet. The FM is just as immature as the rest of the game is, so in a year a test like this one should be better suited.

Of course, but there's also no reason to stay with nothing to do, at least we must know in which atmosfere are we flying... to avoid people whining about bugs that aren't bugs...

Our learning curve is slower than developers speed of work

[kimosabi]

My learning curve tells me that the mixture issue need to be taken care of, and that the FM needs to provide us with more feedback and certain elements of aircrafts behaviour before a FM test is justified. Otherwise mapping an aircrafts performance envelope will not be correct once the FMs have been changed. They know about those issues and I'm sure they are working on it. I'll say it like this: There's no use taking a Fiat Uno to Nürburgring to test lap times, if the race is classed as a FIA GT. But by all means, if you people need something to do just for the sake of doing it......

[ivo]

Bye see here:
http://www.fourthfightergroup.com/eagles/spit2.html

[Peril]

That's useful data on early Spits, thanks.

[Osprey]

I don't know if this ever started or how serious Viper is but I am willing to help with the testing but ONLY if there is some assurance from the development team that it is being taken seriously.

From what I am seeing wider Europe is undertaking a Public Beta test which is adhoc and incredibly disorganised.

So, if we are given genuine co-operation from Luthier & friends, and that we supply genuine reliable information to them to use, then I'm signed up.

[heloguy]

Originally Posted by Viper2000

I suggest that we use the 1976 standard for comparison purposes because this allows us to avoid some otherwise potentially nasty conversions (eg changes to Temperature scales over time...).

Obviously the next thing that we need to do is to find some way of measuring the atmosphere properties on a variety of available maps so that we can pick the best one for testing.

Does anybody have any suggestions as to how we might best go about this?

I would think that the 1976 standard day wouldn't be the best choice as that's not what testing data from the 30's and 40's was based on. Maybe the earlier two would be the best to use.

As far as ambient conditions, either use the gauges in game and hope they are calibrated correctly, or just e-mail the developers to find out what the stock standard atmospheric conditions are.

If there's a way to adjust atmospheric conditions in the FMB (I would look, but will not have my computer with COD for awhile as I'm in the States), then you could create a mission in the FMB that all testers would be compelled to use that are a part of this project.

Really, the best historical data (if it exists) would be that which has variable test data, such as a curve that represents the difference in performance compared to altitude and temperature on the graph axes in order to adjust for density altitude. If this sim has variable weather as it says, then it will be hard to see if the aircraft performs correctly over a range of temps and pressures if it's only tested on a standard day.

[Viper2000]

Originally Posted by Osprey

I don't know if this ever started or how serious Viper is but I am willing to help with the testing but ONLY if there is some assurance from the development team that it is being taken seriously.

From what I am seeing wider Europe is undertaking a Public Beta test which is adhoc and incredibly disorganised.

So, if we are given genuine co-operation from Luthier & friends, and that we supply genuine reliable information to them to use, then I'm signed up.

I haven't started any work on this yet because, as you point out, we're effectively in a public beta at the moment, and with major code changes taking place so regularly the chances are that a lot of the work we put in would be wasted.

I've also got a PhD to finish.

Originally Posted by heloguy

I would think that the 1976 standard day wouldn't be the best choice as that's not what testing data from the 30's and 40's was based on. Maybe the earlier two would be the best to use.

As far as ambient conditions, either use the gauges in game and hope they are calibrated correctly, or just e-mail the developers to find out what the stock standard atmospheric conditions are.

If there's a way to adjust atmospheric conditions in the FMB (I would look, but will not have my computer with COD for awhile as I'm in the States), then you could create a mission in the FMB that all testers would be compelled to use that are a part of this project.

Really, the best historical data (if it exists) would be that which has variable test data, such as a curve that represents the difference in performance compared to altitude and temperature on the graph axes in order to adjust for density altitude. If this sim has variable weather as it says, then it will be hard to see if the aircraft performs correctly over a range of temps and pressures if it's only tested on a standard day.

Using a 1930s or 1940s atmosphere standard is likely to cause confusion, because all sorts of things were different in those days (eg the definition of the Kelvin).

It's also inherently more likely to produce flame wars because if we pick a NACA atmosphere then people will see American aeroplanes with data which looks like primary source data and potentially German or British aeroplanes with corrected data which disagrees with primary sources. We would then find ourselves having to explain the concept of standard atmospheres and correction factors in the face of vociferous accusations of bias from the large population of trolls that inhabit the forum.

Whatever we do, we're going to end up picking a single standard atmosphere so that we can compare the performance of all the aeroplanes in the sim on the same chart. Apart from anything else, if we don't do this, the chances are the somebody else will do so in a biased way with the intention of forwarding their own agenda, since quite a lot of forum trolls seem more interested in being able to say "my aeroplane is better than yours" than in historical accuracy.

Ideally, I'd use the ISO standard atmosphere, because it's neutral and current. However, I don't think that it's freely available, and that would both interfere with testing and lead to accusations that the process was not transparent.

The 1976 US standard atmosphere is freely available on the internet, and avoids most of the risk of accusations of bias it's post-war*, and it is relatively modern (so we get basically modern SI units, though it uses its own private value of the gas constant, presumably for historical reasons).

*Therefore all of the aeroplanes we test will see correction factors.

[CaptainDoggles]

I've got some of my old university textbooks still, one of them has a standard atmosphere in the appendix; I'll check to see which version it is. The textbook is relatively new so it ought to be a modern ISO atmosphere.

[Skoshi Tiger]

Just done a quick check on the Spitfire II, on the ground at Mansten ( 178 feet) the closest I can get in 1 MB increments is a bout 993mb, at Shoreham (7 feet) on the same map 992 MB.


With the current standard SL pressure at 1013 MB it looks like theres a bit of a Low over the South East of England.

Also, FTIW, from the oil temp it's about 21 Degrees.

Cheers

[CaptainDoggles]

Originally Posted by Viper2000

Ideally, I'd use the ISO standard atmosphere, because it's neutral and current.

Just had a look. The appendix in this particular book gives temperature, pressure, density, and speed of sound in SI units and English units. Data are every 2000m up to 70km for SI, and every 5000 feet up to 175000 feet for English units.

Let me know if that's worth anything to you and I'll see what I can do about scanning it.