Bomber Engine Use

[Grendel]

Originally posted by mussie
Many ppl have said that Buffs in WWII never flew at Max Power continuously.

I know if I was in a B-17 flying over Germany in WWII, I sure as hell would want to get in and out as quickly as possible so you would not have seen me running at cruise or normal power unless I had no other choice.

So you would be flying alone, without the protection of your formation or escort fighters. A nice, lonely and easty target for any German fighters.

Plus you would be burning fuel excessively. And damaging your engines. Engines have their limits and especially safe operating limits. Max. power/boost can be used only so long, after that the chance of engine malfunction/damage gets higher and higher.

Better to fly with four working engines, better to fly enough fuel to get home, better to have the protection of your formation and escorts.

[Overlag]

to be fair also, when we DO fly in formations we do have to keep slow to keep tight formations. Just last night we was flying a tight formation of 3 buffs (3x3) and we was running 2100rpm to the target just so we could keep together.

[FiLtH]

Ya we do the same thing. Always seems one guy is lagging behind even with same load.

[Overlag]

Originally posted by FiLtH
Ya we do the same thing. Always seems one guy is lagging behind even with same load.

aye, me and serenity was going along at 2300 during climb, and 2100 once level, and some how flyboy, on 100% all the way, never caught us up lol

[Stoney74]

As far as WEP modeling goes, at least for the actual "water injected" U.S. planes--F4U4 and P-47N, they had water tanks big enough for 10 to 15 minutes of water injection.  The operating instructions said only to run water for 5 minutes continuous.  They could go back into WEP later on until the tank was empty, theoretically.  Even if the tank was empty, they could run at the higher manifold settings--they'd just burn up the cylinders--the water just kept temps down.  Then, they were supposed to record how long they ran the engine on WEP in the log.

Widewing told me once that Pratt & Whitney ran a R-2800 for 48 hours straight at 3000 RPM and 80 inches of manifold, or something like that for whomever was asking about that earlier.

[Golfer]

it's not really the actual running of the engine that causes wear provided cooling and lubrication is there.  It's the starting/stopping and vast temperature changes that cause the most wear.  In turbine engines it's the same thing.  Temperatures spike on startup and the rapid temperature changes do the damage as wear goes.  There's a PT-6 up on the alaska pipeline that's been running for 20+ years non stop.  It'll probably run for another 20 or more.

[mussie]

Originally posted by Golfer
 There's a PT-6 up on the alaska pipeline that's been running for 20+ years non stop.  It'll probably run for another 20 or more.

Hey Golfer

I did a google on PT-6 and from the results I assume your talking about a Pratt & Whitney PT-6 turbine engine

Can you provide a link or some other in on that PT-6 in alaska, Would love to know what they are using a turbine for up there.

Later

[Golfer]

I believe it's used a pump on the alaska pipeline.

I was told about it and it was also explained that is part of the reason it's installed "backwards" on aircraft with the air intake at the rear of the engine.  I cannot confirm that however I'll work on google here later today.

[mussie]

dam that was quick thanks golfer...