Author Topic: TBF...RPM/Manifold (Read 403 times)

Patches · « **on:** May 25, 2004, 10:54:25 PM »

Was flying a TBF last night carrying 2x1k's and 8 rox...was up about 11k and wanted to conserve fuel so I tried to reduce RPM's
but when I did that, the Manifold pressure also reduced without me reducing the throttle. I did this several times and the same thing happened...when reducing RPM's, Manifold pressure also drops at the same time with each key press of the minus key.

My system Specs:

500 Mhz Pentium III
384 Meg RAM
ATI 7200 Card w/ 64 meg Ram
Omega 2.6.37 drivers
Win98SE (4.10, Build 2222)
DX9b (4.09.0000.0902)
ViewSonic VG900b Monitor
1280 x 1024 (32 bit) (optimal refresh rate)

Patches

flakbait · « **Reply #1 on:** May 26, 2004, 12:06:43 AM »

The TBM had a two-stage two-speed blower, and 11k is well before you can use high blower. As a result, the low blower speed can't maintain full power. Pulling RPM back puts more of a torque load on the engine. If you put more of a torque load on the engine after the low blower's critical altitude, it won't be able to hold the same amount of power. As a result, you'll lose some manifold pressure. It happens like this for every aircraft not equipped with a turbocharger. Try the same exact thing with a P-47 and you won't see it because the turbo isn't geared off the engine. The blowers (superchargers) are, so they can only produce a fixed amount of power for a given gear ratio.

-----------------------
Flakbait [Delta6]
Delta Six's Flight School
Put the P-61B in Aces High

frank3 · « **Reply #2 on:** May 26, 2004, 08:21:33 AM »

So that's why the P-47 has such a good performance at high alts!
But what exactly does a turbocharger do? (how does it work)

flakbait · « **Reply #3 on:** May 26, 2004, 11:55:46 AM »

Hit the link in my sig and look under Ground School for detailed info.

-----------------------
Flakbait [Delta6]
Delta Six's Flight School
Put the P-61B in Aces High

frank3 · « **Reply #4 on:** May 26, 2004, 01:35:53 PM »

You wrote all that yourself?

Oh man I love you, I've been trying to teach people these...flying protocol all my AH time!
Not shooting chutes, escort damaged enemy aircraft, leave someone alone when landing/having a beer is just what I always wanted!

You see I can only fly in the H2H, you can understand alot of n00bs buzzing around...Therefor I host/organize missions which have all what you named on your site!

Keep up the good work of civilizing Aces High mate!

Patches · « **Reply #5 on:** May 26, 2004, 02:23:05 PM »

Thank you, flakbait.

frank3 · « **Reply #6 on:** May 26, 2004, 02:56:17 PM »

Flakbait rules

*wonders if he already has a fan club...

flakbait · « **Reply #7 on:** May 26, 2004, 03:14:09 PM »

I wrote it on request. Over the past couple weeks I've had people ask me how this stuff worked. Between that, and Straiga trying to convince everyone he was right and the world was wrong about various things, I thought it was high time someone explained all this stuff correctly. What you see in that Engineering section is the beginnings of a result. I'll be adding more to it when I have the correct info on a few subjects.

And, since we've turned a bug report into a thread about something else... Skuzzmeister, sorry about this, mind moving it over to the Help forum? Thanks!

-----------------------
Flakbait [Delta6]
Delta Six's Flight School
Put the P-61B in Aces High