Jet Engines and Starting Handles

[llondel]

You can tell I've been somewhere again, I'm back with a question.

VS20 from SFO leaving the 6th, we pushed back and sat there for much longer than normal with the engines not running. Then a bloke wearing ear defenders and a hi-vis jacket (and other clothing!) appeared and stuck what looked like a starting handle into the #4 engine, after which they all came to life.

What was that about?

[Rainboe]

Sometimes the start valve which allows HP air into the starter unit packs up. Manual operation effected by sticking a screwdriver into a special hole in the side of the engine to operate the valve manually. He is instructed at the right time to withdraw it.

Better him than me!

[tigger2k8]

Sometimes the start valve which allows HP air into the starter unit packs up. Manual operation effected by sticking a screwdriver into a special hole in the side of the engine to operate the valve manually. He is instructed at the right time to withdraw it.

Better him than me!

seen this done a few times on EI A320's and EZY A319's... needless to say it doesnt look very fun for the engineer as the ones i have seen have had to put a considerable amount of force into it and also get a blast of air to the face :}

[Evening Star]

Just be grateful you did not have to get out and help push start ... sorry, not a helpful reply, but it was too good to resist.:\

[spannersatcx]

3/8 drive handle rotated to open start valve, not too bad on the CF6-80 or the Trent (not sure what the VS20 is operated by).

Worst ever was the JT9 on the 747 as it needed a long thin rod or screwdriver and the hole never lined up with the valve and you ended up with your head getting blasted by the fan exhaust blowing your ear defenders off.:sad:

[llondel]

Thanks for the information, it was an amusing mental picture of using a starting handle on a jet engine as if it was an old car.

I have to admit that once the engines had started, he took an interesting route back away from the engines, presumably to avoid examining one from the inside.

[Skyfan]

Bl**dy hell, wouldn't want to do that more than once. Sounds like a cross between RAC and mission impossible. :ok:

[leewan]

Did it once and one of the scariest experiences I've ever had. Worthy of a try for Fear Factor contestants. The most important thing is removing it at the right time ( starter damage otherwise) and having the composure and presence of mind after such an experience to go out by the right way. A few steps wrong and you're a goner !:\

[avionic type]

from what I remember on the TRistar RB211s we used to "spanner open"the start valve and tell the crew to shut off the air valve in the pylon when the engine reached a certain RPM It was a bit of a bind to do it on the center engine in the tail you had to find a Manlift to get up there without any safety harness as time was the essence for the dreaded slot of take off .HAPPY DAYS!!! Ditto on the 757

[vs69]

All in a days work..... The pylon valve on the CF6 jumbos (PRSOV for the pedants) is a bit more taxing as you need to get up there and be careful not to get caught in/blown away by the cold stream once the things up and running and you try and escape. Just remember your earplugs!

[smudgethecat]

Get a grip ffs, manually opening a start valve is no big deal even F/Os can do it.

[Gargleblaster]

Sounds almost as dangerous as my own attempts at lightning my gas grill !

[Dan Winterland]

I think it would be the 744 on the VS20 so therefore it would be a CF6 engine. As spanners at CX says, it's a 12" extension standard 3/8" drive that fits and it really is no big deal. The valve is actuated by the air presure behind it but electronicly signalled. All it takes is a bit of a turn and then it largely opens itself. There's no danger. The access hole is on the bottom of the cowling. It just takes a bit of co-ordination trhough the intercom between the engineer and the flight deck.

It's a relativley common occurrence.

[CV880]

Going back a few years the Lockheed Electra L188 start valves sometimes stuck closed. There was no "through the cowl method" for manual override so one brought in a set of maintenance steps, opened the RH engine cowl and "tapped" the valve which usually got things turning. One had to quickly close and latch the cowl and remove the steps under the wing to avoid the rapidly accelerating prop. I had to do this once on a number 2 engine (3 and 4 already running) and noticed all the white faces staring at me after I giving the start valve the required technical tap in full view of the left side pax which immediately produced prop rotation and engine start. Probably thought their days were numbered.

[llondel]

I think it would be the 744 on the VS20 so therefore it would be a CF6 engine.

I think Virgin have RR engines on their 744 fleet? This might have changed, but I definitely remember the RR logo on the side on the occasions when I've been in a seat to be able to see that part of the engines. The aircraft in question was G-VHOT if anyone has specific information.

[boeing boeing.. gone]

Virgin uses CF engines, not rollers

[llondel]

True, it's the A346s that have RR. I wonder if the old 742s had RRs, I'm sure I've seen the logo on Virgin engines before, and I've only done four flights in the A346.

[vs69]

Yes a few of the Classics had Rolls Royce donks on them. (But we got rid of them a while back)

[ZOCC]

Hey guys , im an A320 Pilot . Few days back during engine start up we had the start valve stuck in the closed position . So we did the manual start valve procedure and at the next stop they passed it under MEL. While reading the MEL i noticed it said atleast one of the engines must have a properly functioning Start valve. Which made me wonder . if we could do the manual start valve procedure for one engine why not be allowed to do it for both or why not pass both under MEL and continue ?

Any ideas ?

[spannerhead]

ZOCC. This is just a guess but in the event of double engine loss in flight you'd need at least one serviceable start valve to attempt a restart.

[TURIN]

Correct. Inflight re-light. Same on the 737 if memory serves, as a purely windmilling inflight start was/is next to impossible on many engines.

[Dawdler]

On a similar but unconnected note, did the BAC111 engines have a facility for a cartridge start? I ask this because one filthy late afternoon in CPH two BAC111s were stood in for the regular aircraft, (interestingly both flights bore the same flight number, but I digress). One of the engines would not fire up. Captain makes a PA to the effect that he would have to supervise the engine start externally. It was pouring with rain as he went down the aisle. A few minutes later there was an enormous bang and the engine started. Pilot came back a bit wet and off we went.

I always wondered why he had to be outside rather than inside the aircraft at the moment of starting.