Vulcan startup question

[Dougs]

this ones been bugging me for a while why does the vulcan always use the STAD (air compressor) to get started when it has an AAPU (rover GT) on board that will do the job? seems like a lot of hassle to get her up and running?

[Mayfly]

Because whilst the rover was deemed to be capable of starting the engines in practice it didn't have enough oomph and would stall. [I believe]

[Sooty655]

The Rover can't produce enough air to start a 202 or 301, as the starter used with the rapid start option has a higher air demand than the original. The pipework from the Rover to the air header was removed by a modification. So an external air source (Palouste or similar) HAS to be connected to start the first engine.

As soon as one engine is running, it can be used to start the other three, either singly or all together. However, that puts up the turbine inlet temp and thus consumes engine life, so it makes sense to use the external source to start all four.

The only alternative would be to use the rapid start system, which uses high pressure air from on-board storage bottles, and increases the volume further using a combustor system fed with engine fuel. I don't know the state of the system on XH558, but on XM655, although the system is complete, we do not have the bottles charged and don't plan to operate the system.

[Dan4th]

Mister Soots:::::::::::::

I have a few Charged Bottles in my liquor
cabinet I'd be happy to send you.....

What's your quaff of choice??????????

Danf.

[Xplumberlives]

Mister Soots:::::::::::::

I have a few Charged Bottles in my liquor
cabinet I'd be happy to send you.....

What's your quaff of choice??????????

Danf.

NICE offer!

[Jigsaw]

Nice and informative answer

[Crew chief]

Back in 1995 number four engine was started on XM655 using the rapid start system.We tried to start the other three engines off number four but failed due to a slit pipe over number three engine.The damage was caused by a sticky air valve not being closed and the resulting high air pressure also went to number three engine which had not been selected to start so the air had no where to go and found a weak point in the pipe.Both i and sooty do not like the rapid system, its to risky to use on an old aircraft like 655.


cc.

[Hungry Haggis]

I think I recall 558s rapid start had been disabled but was still there not to be used until maybe the last flights of her long life if at all ( Read similar on TVOC a few years ago If I'm wrong someone will be along to put it right eventually) .saying that it would be good to entertain the masses with the rapid start Olimpus chorus in her last flights but I doubt that will happen .If there is that chance of engine damage in one form or other It's far safer not to use it at all .


Wrong comparison i know but why use something that (can/will)damage engines that are in very short supply anyway,Seems like saying have a vintage car (ran on 4star petrol)needs (possibly)expencive conversion to run on unleaded .Ie unleaded petrol can/will damage a pre 1970 engine without conversion--Rapid start on Vulcan can cause damage to a very rare and expencive jet engine .Corect me if I'm wrong in thinking that way.

[Xplumberlives]

Thank you Eric and Mark, very interesting answers from the coalface!

[Jigsaw]

Thank you Eric and Mark, very interesting answers from the coalface!

Hence Sooty?

[Xplumberlives]

Thank you Eric and Mark, very interesting answers from the coalface!

Hence Sooty?

So, when are you appearing on Britain hasn't got ANY talent?

[Jigsaw]

Thank you Eric and Mark, very interesting answers from the coalface!

Hence Sooty?

So, when are you appearing on Britain hasn't got ANY talent?

On a daily basis...obviously

[Dougs]

thanks that answer makes allot of sense always wondered why it took so long to start up

[Nickolas]

Get your self the IRIS Vulcan Sim.
You have to start the thing up by switching it all on yourself. Gives to a better understanding as why it takes so long from crew-in to making any sort of noise. Tons to do.............

[Sooty655]

Get your self the IRIS Vulcan Sim.
You have to start the thing up by switching it all on yourself. Gives to a better understanding as why it takes so long from crew-in to making any sort of noise. Tons to do.............

There is even more to it than that. For example, before the 200v 400hz supply is turned on from the GPU (or AAPP), ALL the 200v loads have to be confirmed to be OFF, in some cases by checking switch positions, and in others by pushing OFF buttons to ensure contactors are really open. That takes a big chunk of time for no actual progress other than ensuring the power can be put on safely.

Then later in the sequence, all those switches are revisited to turn on the particular item at the appropriate time.

[Xplumberlives]

Get your self the IRIS Vulcan Sim.
You have to start the thing up by switching it all on yourself. Gives to a better understanding as why it takes so long from crew-in to making any sort of noise. Tons to do.............

There is even more to it than that. For example, before the 200v 400hz supply is turned on from the GPU (or AAPP), ALL the 200v loads have to be confirmed to be OFF, in some cases by checking switch positions, and in others by pushing OFF buttons to ensure contactors are really open. That takes a big chunk of time for no actual progress other than ensuring the power can be put on safely.

Then later in the sequence, all those switches are revisited to turn on the particular item at the appropriate time.

YES I know, it's GREAT to WATCH!

[Sooty655]

Get your self the IRIS Vulcan Sim.
You have to start the thing up by switching it all on yourself. Gives to a better understanding as why it takes so long from crew-in to making any sort of noise. Tons to do.............

If that is the same sim that Bovril uses, the start-up of the 10 PFCUs is wrong.

So don't jump straight in the real thing on the basis of sim proficiency.

[Nickolas]

The chance to be in the A/c and just watch would be as great an honour as I could ever expect let alone sit in the drivers seat AND be allowed to push some buttons..............

Iv'e been punting around for a set of Flight Reference Cards for ages but can't find any or those that have access to some are reluctant to scan them into pdf flies........

So what IS the correct sequence then Soots??

[Xplumberlives]

The chance to be in the A/c and just watch would be as great an honour as I could ever expect let alone sit in the drivers seat AND be allowed to push some buttons..............

Iv'e been punting around for a set of Flight Reference Cards for ages but can't find any or those that have access to some are reluctant to scan them into pdf flies........

So what IS the correct sequence then Soots??

I vaguely remember someone on the OLD TVOC Forum offering that service, surely they must be available, especially if a donation was made!

[Sooty655]

So what IS the correct sequence then Soots??

PFCUs are started in sets using three buttons at the rear of the P1 side panel ~ first A (originally ailerons) which starts 1,2,7 and 8, then E (originally elevators) which starts 3,4,5 and 6, then R (rudders) which starts both rudders.

The flight sim Bovril uses has the PFCUs started by pressing the stop buttons.

[Xplumberlives]

So what IS the correct sequence then Soots??

PFCUs are started in sets using three buttons at the rear of the P1 side panel ~ first A (originally ailerons) which starts 1,2,7 and 8, then E (originally elevators) which starts 3,4,5 and 6, then R (rudders) which starts both rudders.

The flight sim Bovril uses has the PFCUs started by pressing the stop buttons.

Is that why he doesn't go in the cockpit very often?

[Sooty655]

So what IS the correct sequence then Soots??

PFCUs are started in sets using three buttons at the rear of the P1 side panel ~ first A (originally ailerons) which starts 1,2,7 and 8, then E (originally elevators) which starts 3,4,5 and 6, then R (rudders) which starts both rudders.

The flight sim Bovril uses has the PFCUs started by pressing the stop buttons.

Is that why he doesn't go in the cockpit very often?

He was in the P1 seat for a demo to some visitors last Saturday. He was the one who picked up that the sim was wrong.

[Xplumberlives]

Good man!

[Dan4th]

These are the kinds of things for which the
word "Counterintuitive" was invented!

D.

[Sooty655]

These are the kinds of things for which the
word "Counterintuitive" was invented!

D.

I think it is more that these days we expect things to be intuitive.

You have to remember the Vulcan was designed before the word "Ergonomic" was thought off.