Why start right engine first?
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SF 340.
Left engine first for a GPU start because of reasons given by BH, and because the GPU is usually just behind the right engine, thus running the risk of frying the ramp rat as he unplugs it.
Right engine for a battery start, becase the batteries are on theRHS, so less voltage drop between battery and engine. Also, some aircraft have a prop brake on the right engine which allows it to be used as an APU for electrics and heating (as well as other services) on stand.
Left engine first for a GPU start because of reasons given by BH, and because the GPU is usually just behind the right engine, thus running the risk of frying the ramp rat as he unplugs it.
Right engine for a battery start, becase the batteries are on theRHS, so less voltage drop between battery and engine. Also, some aircraft have a prop brake on the right engine which allows it to be used as an APU for electrics and heating (as well as other services) on stand.
The Reverend
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In a previous life, our start sequence on the 747 was 4, 1, 2, 3. Because of the idle thrust of these engines, if two engines are started on one side first on a wet or slippery tarmac, the tug has great difficulty in controlling the aircraft during pushback.
3,4,2,1. Because that's what they did on Lancasters.....
Watched the start up of a B-52 once - levers all over the place as 2 pilots started a seemingly random selection of the 8 engines each!
Original V-bombers could start all 4 simultaneously, put all the gennies on and switch all the electro-hydraulic PFCUs on - all at the same time!
Watched the start up of a B-52 once - levers all over the place as 2 pilots started a seemingly random selection of the 8 engines each!
Original V-bombers could start all 4 simultaneously, put all the gennies on and switch all the electro-hydraulic PFCUs on - all at the same time!
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Remember seeing a line of Vulcans one day, all quiet one minute then BANG! they wound up in no time and taxied immediately.
From first start to last airborne could only have been a few minutes. Really impressive to watch.
From first start to last airborne could only have been a few minutes. Really impressive to watch.
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From a techie point of view
On our Boeing Fleet
We recommend starting the #2 first especially if using a ground (air) cart. This is because it allows for additional safety in the event of Starter Cutout failing to operate as advertised. There will be at least one isolation valve in the pneumatic system which can be closed to shut-off the air supply to the starter.
The ground cart feeds into the left air supply system.
On our Boeing Fleet
We recommend starting the #2 first especially if using a ground (air) cart. This is because it allows for additional safety in the event of Starter Cutout failing to operate as advertised. There will be at least one isolation valve in the pneumatic system which can be closed to shut-off the air supply to the starter.
The ground cart feeds into the left air supply system.
Paxing All Over The World
With regard to the V-bombers being able to crank all four together .... that would have been something to see - actually to hear. 
As to the bod at the front being able to look back and see what was happening on the wing, is this not another reason for the video camera tucked under the rear fuselage? The point of that was from the BD problem of shutting down the wrong engine but it might also help with starts, i.e. seeing the puff/cloud of exhaust from a jet or watching the spokes go round?
The idea being a camera in a faired pod under the tail, so that it could see wing tip to wing tip. The image would be viewed on one of the glass screens by the mode selector. The camera would be able to see the undercart and it's doors, the engines and the flaps and other flying surfaces on the wing. In the event of dumping fuel, you could (probably) see it streaming away from the vent.
This was also mentioned with the problem of some carriers no longer having ground staff available for inspection of the flying surfaces response to input. Particularly so on the first rotation of the day, or after maintenance.
As to the bod at the front being able to look back and see what was happening on the wing, is this not another reason for the video camera tucked under the rear fuselage? The point of that was from the BD problem of shutting down the wrong engine but it might also help with starts, i.e. seeing the puff/cloud of exhaust from a jet or watching the spokes go round?
The idea being a camera in a faired pod under the tail, so that it could see wing tip to wing tip. The image would be viewed on one of the glass screens by the mode selector. The camera would be able to see the undercart and it's doors, the engines and the flaps and other flying surfaces on the wing. In the event of dumping fuel, you could (probably) see it streaming away from the vent.
This was also mentioned with the problem of some carriers no longer having ground staff available for inspection of the flying surfaces response to input. Particularly so on the first rotation of the day, or after maintenance.
Never flew a Vulcan when 'Mass Rapid' starts were allowed - but we still had the 'combustor' facility on most of them in the late 70s. You parked the throttles at the 50% position, selected rapid start and pressed the 4 start buttons in succession. An uncontrolled fuel/air explosion in the engine combustors spun up the engines in no time at all, as soon as they'd started and the gennies were on you started the PFCUs, 8 seconds later they'd all be running. You briefly cycled the throttles back to idle, then selected full power, turned left a few degrees off the ORP and thundered down the runway. 10-15 minutes later you'd be passing 40 000ft, still climbing...
Mark you, we've done crewroom to airborne in 7 minutes in the dear old Vickers Funbus - most of which was in the bus getting to the aeroplane!
Mark you, we've done crewroom to airborne in 7 minutes in the dear old Vickers Funbus - most of which was in the bus getting to the aeroplane!
Last edited by BEagle; 9th Aug 2002 at 19:22.
Paxing All Over The World
Ah, I wondered if that was what you had in mind. The first aircraft I ever travelled in aged nine, the original VC-10 on a LHR ~ JNB with a fuel stop in NBO. Later we had the Super VC-10 on that run.
In it's BOAC livery, it was simply the most beautiful machine in the air. If I catch sight of one now, perhaps when motoring on the M4 near Swindon, it is enough to endanger the car and my passengers!
In it's BOAC livery, it was simply the most beautiful machine in the air. If I catch sight of one now, perhaps when motoring on the M4 near Swindon, it is enough to endanger the car and my passengers!
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Hi SPANNER-DO,
I find your reasoning quite interesting!
Do you recall that there are, in fact, two pneumatic valves that have to be opened to supply air to the engine starter,
1/ the start control valve, the one you mentioned may malfunction, and
2/ the pylon valve, the one that opens to allow pressure to the start control valve, the one that will only allow reverse airflow, ie, towards the start control valve, when the FE selects that engine to 'ground start'.
Both close, at the same time, when the starter is released.
The isolation valves are not normally used here.
Actually, 4,1,2,3 is the best start sequence of all, taking system operation into account!
Cheers.
I find your reasoning quite interesting!
Do you recall that there are, in fact, two pneumatic valves that have to be opened to supply air to the engine starter,
1/ the start control valve, the one you mentioned may malfunction, and
2/ the pylon valve, the one that opens to allow pressure to the start control valve, the one that will only allow reverse airflow, ie, towards the start control valve, when the FE selects that engine to 'ground start'.
Both close, at the same time, when the starter is released.
The isolation valves are not normally used here.
Actually, 4,1,2,3 is the best start sequence of all, taking system operation into account!
Cheers.
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Hi Flight Detent
Thanks for your response to my previous posting; in which I was refering to the original thread question of why start right engine first then the left as "Glonass" had asked.
I made the assumption (right or wrong) that we were referring to twin engine beasts.
My response was relating to our 752 and 763 fleet.
Sorry for the confusion.
Regards
Spanner-do
Thanks for your response to my previous posting; in which I was refering to the original thread question of why start right engine first then the left as "Glonass" had asked.
I made the assumption (right or wrong) that we were referring to twin engine beasts.
My response was relating to our 752 and 763 fleet.
Sorry for the confusion.
Regards
Spanner-do
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IMHO
Talking about my experience, when I flew light twins (some of them) I started the left engine first when there were daylight and I started the right first when it was dark, because in the nights I couldn’t see prop when it kicked and start playing with the levers, so I had to do it by hear. I preferred to do that because when you start the right first, the passengers used to get scared faster.
When I flew B727 as a F/O, we started 1,2,3 or 3,2,1 depending on the mood, unless we where pushed back with a turn, so we started first the engine inside the turn to help the tug, especially on rainy days.
Now, on the ATR I started the Nº 2 first because it has the prop brake, so it is like starting the APU, nevertheless I (SOP) do not release the prop brake until Nº 1 is stabilized.
When I flew B727 as a F/O, we started 1,2,3 or 3,2,1 depending on the mood, unless we where pushed back with a turn, so we started first the engine inside the turn to help the tug, especially on rainy days.
Now, on the ATR I started the Nº 2 first because it has the prop brake, so it is like starting the APU, nevertheless I (SOP) do not release the prop brake until Nº 1 is stabilized.
