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victorlima01

Simultaneous Engine starts?

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Which engines can be started simultaneously: 1 + 4 and 2 + 3? Or 1 +2 and 3 + 4?Also, what is the correct sequence? from 4 to 1 or the other way around?And last but not least: if I choose to leave one pack running during engine start, which one do I choose? Thanks for the replies guysBest Regards,Victor Limahttp://www.precisionmanuals.com/images/forum/800driver.jpg

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I dont know what the real procedure is I go from out to inner. And the read the manual crap is old get a new line.

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victor lima,i read on there that you should have all packs off, or one on (i usually leave pack 2 on, and 1 & 3 off). some people turn off all packs.as for sequence, the manual states that you can do 2 engine starts at a time: usually, 1 & 4, then 2 & 3 respectively.i start engine 4, then 3. after they stabalise, i start 2 and 1 simultaneously.tom

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Victor,I guess this maybe airline specific but we normally start 4 3 2 1, and one at a time,unless in a hurry for some reason.(although on my sim I normally start 2 at a time).The logic with starting 4 first is you have youe engine driven hydraulic pump working for your primary brake source(sys 4)Packs, we turn 2 and 3 off,sure there`s logical reason why but a good one for me is that it supplies the flight deck with cool air!regardsJon

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Jon, Micahel and everyone else. Thank you for your answers. I saw that on the Virgin DVD as well although I thought I must have been remembering it wrong because for some crazy reason I thought you couldn't start two engines from the same side simultaneously. Ok, so from now on I'll just leave pack 2 on and start 4 + 1 and 3 + 2. My last question now really isn't sim-related but just a curiosity of mine: In real life can you start engines during push back to have them all spooled up to idle by the time the pushback guys are done? I've seen many real-life flights from the flight deck of a 777 but I don't recall seeing the crew ever doing this. Anyway, thanks for clearing it up for me. (BTW I know there are some airporsts such as JFK where you must start the engines at a specific point in the tarmac)Best Regards,Victor Limahttp://www.precisionmanuals.com/images/forum/800driver.jpg

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Victor,Yep, virgin SOPs have changed a little since the days of that DVD so normally start one at a time,if we do have to start 2 at a time it would normally be on the same wing, eg 4+3 or 2+1. I`ve noticed MSFS tends to try and turn you when you have 2 engines on one wing started.It won`t do this in real life but when taxying with number 3 shutdown (to save fuel on taxy in) there is a definate swing you need to correct for on the tiller.Its common practice to start 4 engines during push back,most tugs can take it no problem.But a couple of years ago at LHR egll we had a company notice only alowing 2 engines to be started during the pushback as the tug was a weaker model and was being pushed backwards with 4 engines at idle.You are correct i n that several US airports have start points that you have to be towed to before starting engines,as you say JFK(I`m flying back to LHR from there tomorrow, so will be doing just that) MIA and SFO are other examples.RegardsJon

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I imagine at LAX as well with those long narrow alleys at the TBIT.

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hello guys,Im a customer service rep. for El Al based out of jfk. Alot of times our planes a parked right next to Virgin atlantic's a340s and 744s. I must agree that airports like jfk having pre-located start points for engine starts. Our planes (744s and 777) normally push back to this location before starting the engines. However, just last week I remember looking at a virgin atlantic 744 push back with its number 4 engine already running, meaning they started their engines bfore the pushback commenced. Therefore im forced to say that the decision to pushback and start or start and pushback is up to the captain and atc. In a similar case runway 22 takeoffs at KLGA are rare, but I do see from time to time a nortwest 717 requesting that runway for takeoff.best regards,Gideon

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tom is right, have a look at...PMDG 744 AOM, rev 1.0:(PMDG)page 11-25f: Engine Starter/Ignition SystemsThe Unofficial B744 Simulator&Checkride Procedures Manual:(Mike Ray)page 175f: Engine StartPMDG Boing 744 The Normal Procedures - Deutsches Manual(Jens-Albert Schenk)page 102ff: Enginge Start Procedureetc. etc.greets,Volker

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GideonIn my experience this is usually because the APU is inop. In this situation you would need to have an air start unit to provide high pressure air to crank up one engine. Once you have one turning you can disconnect all the ground equipment and push back then use the running engine to do a crossbleed start on the remaining engines. I fly the B757 (formerly on the 737) so don't know procedures for 4 engine aircraft but it would explain the decision to start one on stand. Kris

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>>>i start engine 4, then 3. after they stabalise, i start 2>and>>1 simultaneously.>>>>this is exactly what the crew of Virgin featured on this ITVV>video did when they were strating their engines.>>Michael J.>http://www.precisionmanuals.com/images/for...argo_hauler.gif>http://sales.hifisim.com/pub-download/asv6-banner-beta.jpgThat`s right. My old man used to start the B744 engines in the order of 4,3, 2 and 1 in that order before in the past. But I have seen I think that it was a Lufthansa B744 at Kuala Lumpur starting 3 and 4 and then 2 and 1 both in pairs a longe time ago. I guess the most you can is 2 at a time. Some start one at a time like my father`s airline Malaysia Airline and as mentioned before Virgin Atlantic.Regards,Alex G

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I fly the B757 so don't know procedures for 4 engine aircraft but it would explain the decision to start one on stand.Two were started on Concorde (2+3) with the aid of ground air on stand (no APU). With two hydraulic pumps on E2 and a pump for the third system on E3, starting both inboards before push provided an opportunity to perform several pre-flight checks on the various flight control channels and systems during the push. Engines 1 and 4 were then started using bleed air off the other two engines respectively once the push was complete.

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Hi JonJust back to the DVD for a mo. Alan C says " this aircraft has an excellent apu and enables us to start two engines at once, which we are doing now with engines 1 & 2". As 4 & 3 are already running are they not creating enough duct air pressure with or without the (excellent) APU ?CheersSteve ps as a matter of interest are they all still with VS on 744's ?

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Air France cargo was at SAT one day, i use to work there, dont know what the heck they were doing there but anyways, when they left they started 3 and 4 and then 1 and 2. was cool, first time seeing a 744F.

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Hi Steve,Got your mail,yes I got distracted by a real flight you were right!In answer to your question,yes you could easily do a cross bleed start with 2 engines going,with only 1 engine you need to use about 70% N2 to get enough pressure.Standard procedures though use the APU to start all 4 using the APU bleed.Alan C has left,Alan R is still around,busy selling cars as a side line! and the other fellow has been on sick leave for years with a bad back(allegedly last seen water skiing in capetown!)regardsJon

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During walkarounds at LAX I watch the guys come off the international termianl. I have seen the one at a time and the 3&4 then 1&2. United starts then 4, 1, 2, 3. My buddy tells me that is because the brakes are on the 4 hydraulics. My question is why is that such a big deal? If I understood the manual correctly the demand pump should provide enough pressure and the 1 & 2 should back it up. And isn't there an accumulator too? Of course I am well aware a fleet program managers whim can make a big difference. We have 737-800s 757/767s and 777 that all have some similar if not identicle systems and we seem to have differnt procedures for each plane.

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"because the brakes are on the 4 hydraulics"If you put HYDR #4 demand on AUX there is enough presure for the brakesTon

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WARNING: This might sound Stupid!On the real manual of the 767 (i know it's a diferent system from the 744) Boeing is quite touchy when it concerns engine hours Vs. startup procedures.There's this procedure that we should use Starter 1 for odd days and Starter 2 for even days. Furthermore, Engine 1 should be started first on even days and Engine 2 first on odd days (it might be the other way around, I don't have the manual with me right now).I read here pilots starting Engine 4 first almost all the times on the 744. How does that interfere with Engine hours and does the real manual have this rather strict code for start up like the 767?I warned you it sounded stupid...

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JohnAre you sure this doesn't relate to ignitor systems? I've heard no such rule on the 757 or 737 but it is recommended to change the ignotors over every sector. This is particularly important in the 737 when we always did the first sector on the Left Ignitor to ensure we could restart from the standby power system in the event of a double engine flame out. This is a no go item and far better find out about it when still at home base and not somewhere down route. It is inevitable that engines will accrue more hours when on the right wing as they are invariably started first but most operators build this in to the maintenance and swap engines round to ensure an even spread of hours although the 90 seconds or so of difference really will not make a thunderous difference over 2500hr standard time between maintenance for the average jet engine. Kris

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Normal Procedures Checklist Boeing 767-200Cockpit Preparation(...)Ignition Switch.............................................SetSet 1 for ODD days, 2 for EVEN days, BOTH for Cold Weather Ops.(...)This is it. Perhaps it got it wrong, since on the same procedures the Engines state "Recomendation: Number 2 Engine First, Except per Airline specification"Is this present in real 744 procedures?

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Hopefully Allan R has picked up a 4th stripe? He seemed to be good left-seat material judging by his FO abilites, very thorough and proactive.

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The only reason I question that logic is because system 1 will provide alternate braking as well as system 2. Demand pumps 1-3 should be in AUTO providing pressure for those systems and 4 should be in AUX providing pressure for 4. There should be adequate pressure for the brakes no matter which engine is started first. Or else I have the system wrong which considering its me that is entirely possible.In the 737 we taxi on engine 1 all the time. Brakes are on the B system which is on engine 2. We still have the electric pump for system B which is less powerfull than the demand pumps on the 747 and alternate brakes on the A system.

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