737-800 SE MACG and additional go around thrust.

[nick14]

Hi all,

So we routinely configure for the no engine bleeds landing for the single engine approach.

My question is what is Boeing performance calculated around, engine bleeds or no for their performance and MACG charts and what is the performance gain/penalty for not doing it?

Thanks

[B737900er]

Nick - Is your SOP to configure no bleed for landing or during SE approaches only , Your statement is not quite clear?

Boeing Performance is based on worst case scenarios. To answer your question its based with bleeds on. Have read of the the Performance Dispatch/Inflight section.

[nick14]

I had a look and couldn't find any wording that stated either way other than the charts having performance decreases for wing anti ice which can only be used with bleeds on so I had a guess at bleeds on.

It's not an SOP it's just historically always been done (probably due to older less powerful a/c hang ups) and I questioned the logic of messing around with it all for very little benefit!

[B737900er]

For overweight landings, hot and high environments or terrain I personally would consider it.

[RAT 5]

I once flew for an operator, B767, who used the above MLW Bleeds OFF, and below MLW bleeds ON for SE approaches philosophy. I think it was CP's answer to a grey question. I then flew for a B737 operator whose SOP, SE, was always Bleeds OFF. There was no note about a serviceable APU or not. In a recurrency session, with F/O as PF (let them manage the operation) with an engine failure & U/S APU this caused some confusion and protracted discussion; because they had not been told what to do. There was a multiple failure of APU + an engine. OMG. My point being that there was an SOP with no education as to why. It didn't matter what the weight was, Bleeds OFF was the SOP. That day we were 10 tonnes below MLW, and I, as captain elected to make the SE landing, eventually(that's another story), but I played the game and let the F/O declare what their plan was. After discussion I elected not to go bleeds off. The SFI(F/O) conducting the session said I was Wrong. My answer was "that is a point of view, and a judgement call."
I could justify my reasoning. They couldn't justify the SOP. I decided to deviate for, IMHO, acceptable reasons.