June 17, 201510 yr 25% N2 or max motoring with a minimum of 20% if 25% is not achievable is what's in our manual. Yep. 25% or max over 20% = give it the gas. Matt Cee
June 17, 201510 yr Yes, start timing when the start valve opens Brendan R, KDXR PHNL KJFK Type rated: SF34 / DH8 (Q400) / DC9 717 MD-88/ B767 (CFI/II/MEI/ATP) Majestic Software Q400 Beta Team / Pilot Consultant / Twitter @violinvelocity
June 17, 201510 yr Well there must be some wisdom in boeing saying that you need to put the start lever to idle at 25% or they would have mentioned to wait till the N2 reached max motoring I'm not sure Boeing do necessarily say that, however (which is the point being made by Andrew). I don't know about the 737, but the relevant section of the B747 (RR) manual start procedure is: Engine START switch .................................................... Pull P2 Verify that the N3 RPM increases. P2 When N3 is at 25%, or (if 25% is not possible), at maximum motoring: FUEL CONTROL switch .......................................RUN looking for a good explanation on what that term means. Motoring = turning the engine over using the starter motor. Maximum motoring = the maximum achievable N2 (or N3 for triple-spool engines) on the starter motor, i.e. when N2/N3 stops increasing. EDIT: everyone else got there whilst I was writing this! Simon Kelsey
June 17, 201510 yr Michael yes! But looking for a good explanation on what that term means.You remind me of Nancy Kerigan. Michael Cubine
June 17, 201510 yr Author You remind me of Nancy Kerigan. Haha why is that? = turning the engine over using the starter motor. Maximum motoring = the maximum achievable N2 (or N3 for triple-spool engines) on the starter motor, i.e. when N2/N3 stops increasing. Good stuff simon Vernon Howells
June 17, 201510 yr So does max motoring vary depending on any conditions? It can but the only time I have seen it reach max motoring below 25% is when starting with an external air cart. Even then most carts will get you above 25% but sometimes you get a lousy one.
June 17, 201510 yr Author Even then the NO. 2 Engine will be started with a cross bleed start. Vernon Howells
June 17, 201510 yr The Continental manual I have says start lever to idle at 25% or max motoring, which ever comes first. Dave Dave Paige
June 18, 201510 yr Even then the NO. 2 Engine will be started with a cross bleed start. How do you suppose #1 got started? By air start cart or by... Obviously you're going to get the required speed when conducting a crossbleed start. The same can't be guaranteed when air start carting the #1 Brian Nellis
June 18, 201510 yr Haha why is that?Vernon Do a Internet search. BTW, I misspelled her last name. It is Kerrigan. "why, why, why?" The last time I saw the post attack video her words reminded of you. It's neither complementary nor derogatory. Just a remembrance. Michael Cubine
June 18, 201510 yr The Continental manual I have says start lever to idle at 25% or max motoring, which ever comes first. Dave Interesting, I didn't know that if you reach 25% then it's ok to go to idle. Most of the time I hit Max motoring around 27%, but if 25% is good enough then no need to wait for MM. Andrew Farmer My flight sim blog: Fly, Farmer, Fly!
June 18, 201510 yr Author How do you suppose #1 got started? By air start cart or by... Obviously you're going to get the required speed when conducting a crossbleed start. The same can't be guaranteed when air start carting the #1 I was just saying, starting NO. 2 you're guaranteed anyway! These are the procedures from my FCOM RW airline SOPs Position engine start lever to IDLE detent when: • N1 rotation is observed and • N2 RPM reaches 25% or (if 25% N2 is not achievable) • at max motoring and a minimum of 20% N2. Max motoring occurs when N2 acceleration is less than 1% in approximately 5 seconds. At 56% N2 RPM, check ENGINE START switch moves to OFF. Do a Internet search. BTW, I misspelled her last name. It is Kerrigan. "why, why, why?" The last time I saw the post attack video her words reminded of you. It's neither complementary nor derogatory. Just a remembrance. Haha thanks alot man Vernon Howells
June 18, 201510 yr Author With this starter motor and the maximum time 2 mins, does this mean i can switch it off and on as many times as i want untill 2 minutes, and then i would need to wait 3 minutes? Vernon Howells
June 18, 201510 yr With this starter motor and the maximum time 2 mins, does this mean i can switch it off and on as many times as i want untill 2 minutes, and then i would need to wait 3 minutes? I'm pretty sure we already covered that, 10 seconds between start attempts. Anyways, tell me just one good reason why would you wanna do that.
Create an account or sign in to comment