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FrenziedAU
04-03-2007, 04:00 AM
I am searching for information about the tempest, specifically the maximum permissible RPMs, and standard combat RPMs.

The engine seems to run at very high revs, and every time I activate the boost it sounds like it's going to leap out of the plane.

What prop pitch settings do people use in it to keep the revs under control, if this is needed?

FrenziedAU
04-03-2007, 04:00 AM
I am searching for information about the tempest, specifically the maximum permissible RPMs, and standard combat RPMs.

The engine seems to run at very high revs, and every time I activate the boost it sounds like it's going to leap out of the plane.

What prop pitch settings do people use in it to keep the revs under control, if this is needed?

OMK_Hand
04-03-2007, 05:17 AM
Hi FrenziedAU.

There's a Tempest V Pilot's notes here:

http://www.airwar.ru/other/bibl_r.html

Even though the numbers don't appear to match, the Ratios between them might be valid?
To this end, converting the rpm and boost as per the max limits in the notes to percentages gives;

Climb: 3050 (95%) rpm +2.2 (85%) boost (1 hour limit in game?) climb to 20,000' = 161 knots.
Max continuous: 2950 (85%) rpm +1.5 (64%) boost
Cruise: 2550 (60%) rpm +.75 (43%) boost

Blower stage 2 at 10,000' or when the Boost drops by 3 lbs (which it does at 10,000).

Whatever is going on with the Tempest, when applied to the game these ratios between 'real' settings seem as good as any, and overheating doesn't appear to be a problem at all, whilst performance is good?

Interesting?

I think I've worked it out right...

The notes limits are (as far as I can tell):

Take off (and combat) 3,700 +7
Climb: 3,500 +6
Max continuous: 3,150 +4.5
Cruise: no lower that 2150, no higher than +3

mynameisroland
04-03-2007, 06:49 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by FrenziedAU:
I am searching for information about the tempest, specifically the maximum permissible RPMs, and standard combat RPMs.

The engine seems to run at very high revs, and every time I activate the boost it sounds like it's going to leap out of the plane.

What prop pitch settings do people use in it to keep the revs under control, if this is needed? </div></BLOCKQUOTE>

Ask Bellator.

FrenziedAU
04-03-2007, 06:51 AM
Thanks for the link, the docs make very interesting reading.
I'll try out those numbers - at least they give me some ideas, thanks.

Viper2005_
04-03-2007, 07:23 AM
Unfortunately there appears to have been a mix up between the Tempest II and Tempest V links.

The Tempest II has a very different engine.

Test reports show that the 1 hour climbing limit for the Sabre IIa engine was 3700 rpm/+7 psi, whilst the combat limit was 3700 rpm/+9.

http://www.wwiiaircraftperformance.org/tempest/tp.html
http://www.wwiiaircraftperformance.org/tempest/tempest-V.html

FrenziedAU
04-04-2007, 03:32 AM
After some quick testing, it seems that in-game full power (110% throttle, WEP on, 100% pitch) equates to 3700 RPM, which is what is listed as combat power. So it seems I can be reassured that my engine is not going to leap out of my plane at that speed, at least for 5 minutes.

stathem
04-04-2007, 03:56 AM
Oh Yeah, balls to the walls and don't spare the con-rods.

The Tempest's Napier Sabre was a little different to most a/c powerplants of the era. Being 24 cylinders, sleeve valved and quite short stroke for a large engine of the time, it could take much higher revs.

After the overheat msg comes on, you've got about 5 minutes before it breaks.

mynameisroland
04-04-2007, 04:46 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by FrenziedAU:
After some quick testing, it seems that in-game full power (110% throttle, WEP on, 100% pitch) equates to 3700 RPM, which is what is listed as combat power. So it seems I can be reassured that my engine is not going to leap out of my plane at that speed, at least for 5 minutes. </div></BLOCKQUOTE>

Later versions of the Sabre than the one we have was capable of 4000 rpm - and around 3040 HP. Ingame it is best to run the engine with lower prop pitch settings in level flight and cruise and save the 100% for combat and climbing turns. Always run with the WEP engaged unless deliberately trying to cool the engine. I can cruise at 570 km/h at sea level with trim and clever engine managment. This still leaves me with a big power boost for dogfights and a relatively cool engine.