I know it is common practice to start the right (2) engine first, just wondering what is the reason for this? Not disagreeing with it at all, just trying to expand my knowledge. Thanks

Just a guess but I believe it is because it is away from the entrance door. Tom

Simon Holderness (the SA pilot that posted that great description of real world ops) said he always started the downwind engine first.

Isn't it something to do with hydraulics being supplied from the right engine? Or something like that?

Isn't it something to do with hydraulics being supplied from the right engine? Or something like that?

The electric pumps will provide this before engine start.

Simon Holderness (the SA pilot that posted that great description of real world ops) said he always started the downwind engine first.

I wonder what happened to Simon, he's gone quiet.

The AS procedure is to start number 2 then number 1. Used to be the other way around but was changed a few months ago. Ill see if I can find the bulletin explaining why.

I thought it also had to do with direction of push back for safety of the ground crew?

Originally - back in the time of propliners - it had to do with the captain not being able to see the nr 2 engine - so he had to hear it starting up. After #2 got started OK he could start number 1 - which he could see himself.Can't remember where I read that but it sounds logical. I guess they just kept the procedure of starting number 2 first.

I'm still here! Just really busy at work :) Also, most questions here are answered pretty well by the collective knowledge actually. It's our company policy (as stated above) to start the downwind engine first - exhaust gases will then be blown away from the pack inlet in the wing root (we hope), and not get that lovely JETA1 smell in the cabin (mmmm!) To be honest, it doesn't really make that much of a difference, and I've never really found any technical reason why one should be started before the other. Some other reasons could include - starting the #1 first since the engineer is normally walking along on the F/O (#2) side, and it minimises his exposure to working in close proximity to a running engine, starting the #1 during a ground air start (since the engineer must walk in and decouple the connection after the #1 start, similar situation), equalising running time on each engine (although airframe hours are the ones that get counted I guess) and.....er....thats about all I can think of. It is our company policy (and indeed might be down in black and white from Boeing somewhere) to NEVER start an engine while passengers are boarding, or even while any main exit or cargo door is open.

The packs ram doors are used only for cooling, air for passengers is taken from the engine air, so, only if you have tail wind you could put exhaust air into the cabin, also, if in tail wind conditions, it is better to rotate the aircraft to prevent N1 rotation in wrong direction before start and to prevent possible compressor stalls during the starting sequence.Other things to let the eng 2 start first: In normal condition APU is feeded by the left tank, starting ENG2 before ENG 1 will add fuel consuption to the right side, balancing the APU burned fuel from the APU start up.In case of problems, shuting down the right engine (or not) will not have influences to a possible airport stair positioning on main entry doors.APU bleed feeds the left side of te pneumatic duct, engine 1 also, a dual bleed condition that could be prevented starting the right engine first. (yes, it's almost the same as with isolation valve open) but by closing ISOL VALVE you wil mantain pressure on both sides (if needed engine can be spooled up to increase it's bleed pressure). Closing ISOL VALVE with eng 2 already started will let you to start the left engine without problems.

Ugh, completely correct about the inlets in the wing root of course, brain failure......this is what too much work does!

wow, what a wealth of knowledge from what I thought would be a simple question, simple answer. Thanks to everyone.

This may have been mentioned already, but if you start #2 first, you can isolate the right side and use engine bleed and the pack immediately. Useful in Fairbanks and Phoenix.

Useful in Brazil as well. As a matter of fact, Gol airlines´ SOP is to start #2 engine and immediately close the isol valve and turn on right pack (which will be fed from #2 engine whille APU provides bleed air for #1 engine start.)