737NG landing gear retraction
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737NG landing gear retraction
Hey fellas,
following question regarding 737NG gear retraction:
In a scenraio, you loose ENG 1 during T/O, so gear retraction during climb out is ensured through the LGTU. Then, while in-flight, you experience a loss of HYD SYS B.
Question: In this event, will the landing gear retract during an one ENG INOP go-around or not?
Looking through the books, I found alot of stuff about the LGTU and it's ability "... to raise the landing gear at the normal rate when system A engine-driven pump volume is lost." But no word about the non-normal combination of having experienced an ENG 1 failure and LOSS OF SYS B.
I guess what I'm trying to ask is: Does the SYS A ELEC pump provide enough fluid volume to opearte (retract) the landing gear?
Please enlighten me on this one.
following question regarding 737NG gear retraction:
In a scenraio, you loose ENG 1 during T/O, so gear retraction during climb out is ensured through the LGTU. Then, while in-flight, you experience a loss of HYD SYS B.
Question: In this event, will the landing gear retract during an one ENG INOP go-around or not?
Looking through the books, I found alot of stuff about the LGTU and it's ability "... to raise the landing gear at the normal rate when system A engine-driven pump volume is lost." But no word about the non-normal combination of having experienced an ENG 1 failure and LOSS OF SYS B.
I guess what I'm trying to ask is: Does the SYS A ELEC pump provide enough fluid volume to opearte (retract) the landing gear?
Please enlighten me on this one.
Last edited by cloud_chaser; 2nd Mar 2013 at 19:22.
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The answer is in your post. The electric hydraulic pump it's not enough to raise the gear at a NORMAL rate, so the answer is yes, but slower than normal; in this scenario you might not be able to comply with the minimum climb gradient.
As far as I remember the volume ratio between the engine driven pump versus the electric one is 6 to 1.
As far as I remember the volume ratio between the engine driven pump versus the electric one is 6 to 1.
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FB,
thanks for your reply. I was suspecting the ELEC PUMP to be capable of retracting the gear (although at slower rates), but I could not find any written confirmation thereof.
By the way, the fluid volume ratios between ENG DRIVEN and ELEC Pumps that I came across was 4 to 1.
Again, thanks for the hint.
thanks for your reply. I was suspecting the ELEC PUMP to be capable of retracting the gear (although at slower rates), but I could not find any written confirmation thereof.
By the way, the fluid volume ratios between ENG DRIVEN and ELEC Pumps that I came across was 4 to 1.
Again, thanks for the hint.
