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XyZspineZyX
09-21-2003, 10:27 PM
Ok here we go!!

The test 4 A/C all with Rad closed, 110% throttle,100% Fuel and default loadout.

WS a/c 100% prop,100% mixture,supercharger stage 1.
LW a/c auto prop,wep.

On-line Summer and Winter map,(WIND TURNED OFF) takeoff from far southwest base fly heading 250. Speed bar altitude 0 sea level,no cockpit dial altitude 10 to 15 meters.

Speed reading from speedbar=(SB)
Speed readings from airspeed gauge=(ASG),(no cockpit view)
All speed (kph) +.- 3kph


_______Winter Map______Summer Map

109K____ASG=558________ASG=580
__________SB=570_________SB=570

La7(3x)__ASG=582________ASG=600
__________SB=600_________SB=590

Yak-3____ASG=543________ASG=562
__________SB=560_________SB=550

190D-45__ASG=578________ASG=595
__________SB=600_________SB=580


This test was just to get a flat out speed run all A/C flown for 5 minute (109K for about 2.5 then overheat) to get the top sea level speed.

Don`t know about anyone else but the speeds look a little different for the Summer and Winter Maps.

Question: I`ve hard some ppl say that the airspeed gauge in the (no cockpit view) is indicating True A/S?

If that is true then there is a problem because TAS is never below IAS! Maybe in an extreme situation like a hurrican off-shore! And normally TAS and IAS are the same at sea level.

I`ve taken off from Airports in the Southwest US that are at S/L and below in hot/cold temps and never had TAS higher then IAS by more then 1 knot.

Not bashing anyone here just saying that the speeds are jumping all over the place and don`t seem to hold any pattern.

Any ideas???

~S~



Message Edited on 09/21/03 09:30PM by Cooler07

Message Edited on 09/21/0309:30PM by Cooler07

XyZspineZyX
09-21-2003, 10:27 PM
Ok here we go!!

The test 4 A/C all with Rad closed, 110% throttle,100% Fuel and default loadout.

WS a/c 100% prop,100% mixture,supercharger stage 1.
LW a/c auto prop,wep.

On-line Summer and Winter map,(WIND TURNED OFF) takeoff from far southwest base fly heading 250. Speed bar altitude 0 sea level,no cockpit dial altitude 10 to 15 meters.

Speed reading from speedbar=(SB)
Speed readings from airspeed gauge=(ASG),(no cockpit view)
All speed (kph) +.- 3kph


_______Winter Map______Summer Map

109K____ASG=558________ASG=580
__________SB=570_________SB=570

La7(3x)__ASG=582________ASG=600
__________SB=600_________SB=590

Yak-3____ASG=543________ASG=562
__________SB=560_________SB=550

190D-45__ASG=578________ASG=595
__________SB=600_________SB=580


This test was just to get a flat out speed run all A/C flown for 5 minute (109K for about 2.5 then overheat) to get the top sea level speed.

Don`t know about anyone else but the speeds look a little different for the Summer and Winter Maps.

Question: I`ve hard some ppl say that the airspeed gauge in the (no cockpit view) is indicating True A/S?

If that is true then there is a problem because TAS is never below IAS! Maybe in an extreme situation like a hurrican off-shore! And normally TAS and IAS are the same at sea level.

I`ve taken off from Airports in the Southwest US that are at S/L and below in hot/cold temps and never had TAS higher then IAS by more then 1 knot.

Not bashing anyone here just saying that the speeds are jumping all over the place and don`t seem to hold any pattern.

Any ideas???

~S~



Message Edited on 09/21/03 09:30PM by Cooler07

Message Edited on 09/21/0309:30PM by Cooler07

XyZspineZyX
09-21-2003, 10:34 PM
its a little off the TAS to IAS...ok

I guess FB models engines running better at warmer temps which is great!!!



Message Edited on 09/21/0305:34PM by Wolfstriked

XyZspineZyX
09-22-2003, 02:29 AM
Your summer map SB numbers seem pretty close to the object viewer speeds. They are about 10km/h less than object viewer for sea level. Seems pretty close and maybe someone else will repeat your tests and provide some contrast to the findings. If I get a chance tonight, I'll try to match your settings and see what I get.

I thought I read that due to the thinner air in Winter, the planes were faster during that season. Thought I read that here in the ORR. I could be wrong./i/smilies/16x16_smiley-indifferent.gif

_______________________________________
çk?¯kT 2003**

XyZspineZyX
09-22-2003, 03:20 AM
Air would be thicker during winter as Colder temperatures means less thermal kinetic energy and therefore higher density.

SlickStick wrote:
-
- I thought I read that due to the thinner air in
- Winter, the planes were faster during that season.
- Thought I read that here in the ORR. I could be
- wrong./i/smilies/16x16_smiley-indifferent.gif
-
- _______________________________________
- çk?¯kT 2003**



http://www.redspar.com/redrogue/CraggerUbisig.jpg

About after 30 minutes I puked all over my airplane. I said to myself "Man, you made a big mistake." -Charles 'Chuck' Yeager, regards his first flight

XyZspineZyX
09-22-2003, 04:53 AM
Cragger wrote:
- Air would be thicker during winter as Colder
- temperatures means less thermal kinetic energy and
- therefore higher density.
-

Ok, good to know. I should have thought a bit more on that one and harkened back to my Physics course.

Oh yeah, I didn't finish that one./i/smilies/16x16_smiley-wink.gif

_______________________________________
çk?¯kT 2003**

XyZspineZyX
09-22-2003, 05:03 AM
Ok! At least someone responded thanks!

But there are a few things here gents.

First I`m still trying to find out if they are using the A/S dial in the no cockpit view as TAS (true airspeed).

If this is so then there is alot wrong here with the speeds.

1: TAS is never below IAS, unless there is some big instrument error or it took a few rounds in the static system and the mechanic never fixed it.

2: TAS and IAS are always the same with some basic instrument error +,- 2 knots at sea level.

3: Cold or Hot doesn`t matter at sea level the pitot static system reads the same ram air, And the standard pressure for sea level is 14.7 psi just about everywhere, unless you modify the area with a High or Low pressure system.

Just a guess but I don`t think Oleg would have programmed in frontal systems with High/Low pressure!!!!


I`m not looking for the perfect settings here because in RL you don`t have them anyway but! Seeing speeds off from each other as far as 22kph and looking at the switch the speeds are doing from (winter/summer) doesn`t look right.

So I ask this are we suppose to use the speeds in the game viewer for summer only?

Hey 5 to 10 kph I can live with but not the 22kph difference and not the different readings from summer and winter maps.

Some others really need to look at this.

~S~

XyZspineZyX
09-22-2003, 05:55 AM
I thought that the loss of speed in awarmer climate will cause less horsepower to be developed and so it will go slower?Dunno but as long as all planes see a reduction than its alright i guess.

XyZspineZyX
09-22-2003, 07:11 AM
Yes there is a loss of HP with a higher temp, this is because of less air density, you will normally see this at high altitude airports on take-off or landing.

But it does not change how the pitot,static system works for air speed indaction. That is dynamic pressure in the pitot tub or ram air input.

This is why I`m saying that the speeds for ALL aircraft are off more then just alittle.

The differences between TAS and IAS and Winter/Summer are just not right.

~S~

XyZspineZyX
09-22-2003, 09:59 AM
Pitot system may not be different but the colder air does make better lift and prop thrust efficiency. Ask a pilot sometime, it's one thing they learn. Even the difference between day and night temperature can be noticeable. On a really hot day you will not be able to take off with as much of a load, large jets or small propjobs. Even your takeoff runs should vary with temperature.


Neal

XyZspineZyX
09-22-2003, 06:04 PM
I am one!

I`m not saying that Hot/Cold air doesn`t affect aircraft performance or take-off and climb performance, high temp and high altitude makes for High density altitude performance
changes!

What I`m saying is that TAS and IAS at SEA LEVEL are not different from eash other. The pitot system reads ram air induction pressure not air density.

~S~

XyZspineZyX
09-22-2003, 06:24 PM
No they shouldn't be makes sense to some degree. I do know that with normal weather there's always a few millibars to 10's of millibars pressure difference although I'm unsure of how that translates to standard pressure altitude differences. Have you heard of any differences between rainy low pressure weather and sunny high pressure weather? Is there a real TAS guage you can use and compare to IAS? Because ram air at 1000 ft altitude is going to show a 2% (or a bit less) lower IAS from TAS only because of the lower density so wouldn't it follow that there will always be a variance due to air density?

Other than that, which in most cases is only academic in the sense that measureable doesn't mean significant then what could this mean in the sim? Is it a no-cockpit guage or speedbar problem, perhaps? Or could it be something right down to the flight physics and a product of the tweaking to meet the damned charts? Those are questions I guess only Oleg and MG can answer but I am sure that the differences do mean a lot to the outcome of how the speed and climb tests are run.


Neal

XyZspineZyX
09-22-2003, 06:57 PM
Yeah I don`t think there`s any real big modeling of weather systems in the sim, and as I posted earlier I give it 5 to 10 +,- kph for error.

But as can be seen in the speed chart (1st post) some A/C are off by as much as 20 plus kph. This will have an impact on climb rates.

And the TAS should always be at or higher then IAS on all maps.

~S~

XyZspineZyX
09-22-2003, 07:31 PM
were WWII planes airspeed indicators that precise,
I have read in several books that they were not.


VICTOR MAY HAVE BEEN A WEIRDO,BUT HE WAS A DAMN GOOD FIGHTERPILOT.
<ceter>http://www.boners.com/content/788904.1.jpg </center>

XyZspineZyX
09-23-2003, 05:41 AM
Like I said I`ll give it 5 to 10 kph and would be happy.

But 20 to 25 kph off No! And if it`s true, that the dial A/S gauge in the no cockpit view is reading TAS then the speeds are OFF.

And I hate to say this but anyone doing testing might want to do the same test (climb) on winter maps.

From what I`m getting all A/C are off not just a few.

I`m just asking someone here anyone, do the same test (setting at top of post) in the winter and summer maps and look at the speeds for sea level top speed, not that the speed are off from the game viewer, but the difference in TAS and IAS at sea level for winter and summer maps.

There should be no measurable difference AT SEA LEVEL between the TAS and IAS speed.

And one things for sure TAS is NEVER below IAS.

Gents this is a bug. And to say that it`s acceptable flight modeling is wrong.

By the way in real life there`s not a gauge in any A/C that gives read outs in TAS directly.

TAS is computed from IAS to CAS to EAS=TAS.

Note: Remeber I said SEA LEVEL so you don`t need altitude and temp.

Unless we have FMS`s in these things, thats the only way to get TAS number read out.

~S~

XyZspineZyX
09-23-2003, 09:52 AM
-
- I`ve taken off from Airports in the Southwest US
- that are at S/L and below in hot/cold temps and
- never had TAS higher then IAS by more then 1 knot.
-
- Not bashing anyone here just saying that the speeds
- are jumping all over the place and don`t seem to
- hold any pattern.
-
- Any ideas???
-
- ~S~
-

The throw a 40's IAS speedometer in your plane and you will see bigger differences. The systems have evolved in the past 60 years.

In other parts of your post you are correct imo. theres inconsistencies as mentioned. Some might be explanied by air temperature/density variation but not sure how much that would account for.

XyZspineZyX
09-23-2003, 06:10 PM
Right! Now we have to take into account that airspeed indicators in the 1940`s can have large differences because they are 60 year old technology!

LMAO!!!!!

XyZspineZyX
09-23-2003, 06:31 PM
In a sim where every plane starts in perfect condition as was made then the AS guage should be as good as they made them in those times. They were good enough for the tests that were made and much better than WWI guages. It should be noted somewhere what few percent if that much that a new, working, calibrated AS guage from the 40's was off, how many % at high speed of SL full speed flight.

WWII wasn't the Flintstones, the Montgolfiers or even the Wright brothers. From what I read the big errors were in highspeed dives where the planes approached 700kph and higher which would indicate that compression was keeping some of the pressure from reaching the pitots.


Neal






Message Edited on 09/23/0301:37PM by WWMaxGunz