kontiuka Posted October 14, 2014 Posted October 14, 2014 I know in just normal flight you don't NEED to have the fuel booster on but is there any harm in just leaving it on during flight? I'm asking because in the manual it says to turn it on before you begin your landing approach. This implies you would have a reason to turn it off during flight.
effte Posted October 14, 2014 Posted October 14, 2014 If you read carefully, it doesn't say to turn it ON, it says to CHECK that it is ON (or EMERGENCY, if available). That's a world of difference. ;) Nowhere does the manual tell you to turn it off in flight. It stays on. Cheers, /Fred ----- Introduction to UTM/MGRS - Trying to get your head around what trim is, how it works and how to use it? - DCS helos vs the real world.
kontiuka Posted October 14, 2014 Author Posted October 14, 2014 (edited) ok. Just slightly ambiguous language I guess. Could be interpreted as a direction similar to the first item in the checklist, as in "set the fuel booster pump to on". Approach Check When approaching the field for a landing, perform an approach check, which includes the following steps: Fuel –select fullest internal tank for landing. Fuel booster pump – set to ON. Edited October 14, 2014 by kontiuka
Iberian Posted October 14, 2014 Posted October 14, 2014 ok. Just slightly ambiguous language I guess. Could be interpreted as a direction similar to the first item in the checklist, as in "set the fuel booster pump to on". Approach Check When approaching the field for a landing, perform an approach check, which includes the following steps: Fuel –select fullest internal tank for landing. Fuel booster pump – set to ON. Take it in its literal sense, during approach "check" that the fuel booster is set to on. [sIGPIC][/sIGPIC]
Paganus Posted October 14, 2014 Posted October 14, 2014 It should never be turned off during normal operation. The engine does have a mechanical pump but if the engine shuts off and the pumps are off you will have no fuel pressure, and won't be able to restart. Also when operating the engine at or near maximum you want both due to the high fuel demand. This is why you are limited when running on drop tanks. They don't have pumps and run off the engine pump and a little bit of vacuum.
kontiuka Posted October 14, 2014 Author Posted October 14, 2014 Take it in its literal sense, during approach "check" that the fuel booster is set to on.Agreed. Just a little grammar structure problem in the list. An otherwise excellent manual though.
effte Posted October 14, 2014 Posted October 14, 2014 You might also want to read this post by yours truly from the other day. It provides a bit more on when, how and why. In the real manual (AAF 51-127-5, Aug 15 1945), it states to "make the following checks", and then "put the fuel booster pump switch at ON". Never really considered the wording - that's just the way they're usually/often written I'd say. I see how it can be read your way as well though, so yes - I guess it is indeed slightly ambiguous. Another suggested read is the fuel system section of the above real manual as well. On pg. 21 you have a bit more on why and how. Cheers, /Fred ----- Introduction to UTM/MGRS - Trying to get your head around what trim is, how it works and how to use it? - DCS helos vs the real world.
Mike Busutil Posted October 18, 2014 Posted October 18, 2014 (edited) Notice in this video of a real P-51 he turns on the fuel pump at the 5:13 mark. Notice the switch is Off in the up position and On in the down position, You can see the fuel pressure come up when the switch is moved to the down position (On) Then notice after takeoff in this video, he turns off the fuel pump at the 1:50 mark and verifies the fuel pressure is good. The fuel pump is then turned back on at the 6:14 mark before landing. Edited October 18, 2014 by Mike Busutil [sIGPIC][/sIGPIC] Checkout my user files here: https://www.digitalcombatsimulator.com/en/files/filter/user-is-Mike Busutil/apply/
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