Vulcan Bomb-bay question

[sooty655]

On the B2 Vulcan (or at least on some of them) there is a bowden cable arrangement connecting a lever on the emergency bomb-bay door selector valve to a pull-ring in the No 3 engine bay.

What was it for and/or when would it be used?

[forget]

:confused: Do you have any theories what it might be for?

[BEagle]

Was this just on aircraft modified to carry the Blue Steel missile?

[sooty655]

Was this just on aircraft modified to carry the Blue Steel missile?


Don't know - the aircraft I have seen it on is XM655 which was built with the Blue Steel mods, but then unmodded. The arrangement is still there.


Do you have any theories what it might be for?


If opened, the bomb doors would hit the open engine doors, so it could be to prevent accidents. However, the same clash could occur with the No2 engine doors, and there is no similar provision on that side.

So the short answer is No, we haven't any sensible idea at all.

Sooty

[forget]

If opened, the bomb doors would hit the open engine doors, so it could be to prevent accidents.

Don't think so. The doors never go beyond the edge of the bomb bay. Could be wrong. Anyway, such a kit wouldn't be fitted to prevent a hangar cock up. Chiefs were for that. :bored:

http://i21.photobucket.com/albums/b270/cumpas/Untitled-2-7.jpg

PS. XM655 which was built with the Blue Steel mods, but then unmodded.

Is that right? I was at Cottesmore when 655 was delivered new. So far as I know the entire final batch was never intended to be Blue Steel. :confused:

[BEagle]

The Blue Steel was fitted with an emergency dump valve, to release the HTP into a water pit in the event of a fire.

I wonder whether this ring pull device was in some way connected with the emergency HTP dump system?

[sooty655]

So far as I know the entire final batch was never intended to be Blue Steel.


Might be wrong, I came to Vulcans very recently, but our understanding is that 655 was modded in production, then demodded before delivery.


Chiefs were for that.


Yeah, that's why I said we hadn't got any SENSIBLE ideas. :)


I wonder whether this ring pull device was in some way connected with the emergency HTP dump system?


No3 engine bay would seem a strange place to put it.

In its present configuration, the ringpull moves a lever which presses on one of the manual buttons on the emergency bomb door selector valve. I don't know whether it is the Open or Close button, but I will trace the pipework next weekend to find out.

The arrangement doesn't appear in any of our fairly comprehensive manuals, but they have been collected over the years, and don't necessarily reflect our specific aircraft.

Sooty

[flipflopman RB199]

Hi Sooty,

The set up you describe is not only limited to Blue Steel Vulcans and indeed XH558 is also fitted with exactly the same arrangement.

The ring pull is designed so that the Bomb Bay door emergency solenoid can be manually operated to open the bomb doors without requiring electrical power. The selector valves used on the Vulcan, and other aircraft of the time, were able to be manually operated to move the shuttle valve inside the selector, thus giving hydraulic flow one way or the other. As you say, the ring pull connects to a lever which depresses the OPEN side of the actuator, thus allowing the doors to be manually opened. Why you would specifically want to do this, I can't tell you, however provision was made for it, and it was an item that we had to functionally test and sign for when we rebuilt 558. Having rebuilt the Hyd system personally, I am pleased to confirm that all worked as advertised!! :p

Hope that clears that issue up.


Flipflopman

[forget]

Bingo! :ok:

Pleased to see you're still around FFM.

[sooty655]

Thanks for that, FFM.

I assume the idea would be for one guy to pull the ring, and the rest of the crew to haul on the doors.

Since the ring is in the No 3 engine bay, I guess that the sooty pulled the ring, thereby avoiding any real work. :)

Seems like an ideal arrangement to me. :D

Sooty

[BEagle]

Thanks for supplying the answer, FFM!

Are you still working on '558?

[forget]

....... and the rest of the crew to haul on the doors.

No need for any hauling, shirley? The ring pull would only be used with no electrics to drive the solenoid valve for the bomb bay jacks hydraulics. The ring pull manually opens the valve for the hydraulics. No? Or am I missing something? FFM?

[sooty655]

The ring pull is on the emergency selector valve. If you have no electrics, you also have no pump. The main pumps wouldn't feed through the emergency valve.

Sooty

[forget]

How about plugging a hydraulic rig into the bomb bay jacks? Take an aircraft in hangar with no electrics allowed due maintenance. Need the bomb doors open?

[sooty655]

Hydraulic rig connects to main system. If that was the intention, ringpull would be on the main system valve, which would have been just as easy, but it ain't what we have got.

Sooty

[flipflopman RB199]

Hello again!

Thank you very much for your kind words. To answer a few questions, sadly I'm not still working on 558, but remain on very good terms with TVOC and the lads currently looking after her and I'm delighted with the current news. I tend to be around here most days, but as I'm no longer aware of the day to day dealings with 558 and TVOC, it's not really my place to join in with much of the rumour and speculation which surrounds the project!

Anyhow!

It's a little of both really, regarding the hauling on doors! The Emergency system for the Bomb Doors is almost a small seperate system that has a constant bleed to the main return line, so that useage of the Emgy system does not impact upon the normal operation of the doors. This means that when the solenoid is manually operated, a few sturdily built chaps hanging off the doors, will open the doors and the Hyd fluid will be routed via the Emgy solenoid, back into the main return line. Forget is also completely correct though, in that with a Hyd rig connected to the aircraft, the manual ring pull can be used to open the bomb doors without electrical power being required.


Hope that answers more questions than it raises!! :p


Flipflopman

[sooty655]

Hope that answers more questions than it raises


It certainly does, and thanks again, FFM

However, it does raise one.


with a Hyd rig connected to the aircraft, the manual ring pull can be used to open the bomb doors without electrical power being required.



Can't get my (admittedly geriatric :confused: ) brain around that one. I don't think hydraulic pressure from a (normally connected) rig would be routed to the bomb door rams via the emergency valve.

I haven't got a hydraulic system diagram at home, so I will have to wait till next Saturday to check it out at Wellesbourne.

Sooty

[forget]

Sooty, Slight thread drift here. I see from the 558 web 655 Maintenance & Preservation Society - History (http://www.xm655.com/history.php)
that ‘Even the ECM gear was left in, and the ECM bay is 100% complete. Work on the bay is continuing to bring it back into fully working condition’.

Interesting, and I’m all for this sort of thing - but that’s a non starter. Even if the Red Shrimps and (presumably) X Band still worked (which they won’t, trust me) turning them on these days could zap untold new microwave systems.

For what it’s worth – here’s what I’d do. The ECM equipment, inside, is a work of ‘60s electro mechanical beauty. All systems are in pressurised ‘dust bin’ cans which may be easily sectioned to show the innards. They’d make a helluva static display in the hangar. Maybe you don’t do static displays - but Newark ought to. I’ll be visiting you when the weather cheers up and I’ll give you a call to show you what I mean. If you ever do section them, take your watch off first. The Carcinitron magnets in the Shrimps will suck a spanner across the hangar. ;)

[Blacksheep]

Time for a quiz.

Your starter for ten.

Q. Why might you wish to open the bomb doors without applying electrical power? :uhoh:

[forget]

How about in the hangar when the electrics can't be 'On' because of - think of any one of a dozen reasons.

[sooty655]

‘Even the ECM gear was left in, and the ECM bay is 100% complete. Work on the bay is continuing to bring it back into fully working condition’.



That page of the website was written an awfully long time ago, and maybe also with an element of wishful thinking. There is now no intention to power up any of the ECM gear.:)

We do still have the complete suite, although the two forward cans are normally left out to shift the cg forward and ease access to the rudder pfcus.

We did once have an AEO power up the glycol pumps with incomplete pipework, which made a nice mess.:ugh:

Sooty

[Blacksheep]

Nope.

A clue.

The aircraft would not be in or near a hangar. It would be on the far side of the airfield, all on its own.

[forget]

It would be on the far side of the airfield, all on its own.

On the far side of the airfield it wouldn't be 'on its own'. Every pan had a king size GPU, and if the aircraft was out of the hangar then the electrics were buttoned up and useable. Next?

[Blacksheep]

Next?

The duty armoury team would be crouched behind the GPU, fingers in their ears, while their electrician's mate gingerly approached the aircraft.

[sooty655]

Bomb off the rack and lying on the doors ?????

[Blacksheep]

Or far end of the Sunspot dispersal, no GPU 'cos the Malties have all gone to church, and the crew chief wants to get his bike out of the pannier.

Lots of reasons why you might need to open the bomb doors without electrical power. Including removal of a hang-up.

[sooty655]

But neither a bomb hang-up nor a crew chief's bike would explain why CAA required FFM to make it work on 558. It would have been much easier to take it out, like all the other stuff which was junked.:ugh:

Sooty

[sooty655]

Having given all the explanations above some thought, I have a suggestion.

Maybe the idea was not specifically to be able to open the bomb doors without electrical power available, but that by doing it manually, it was possible to open only ONE door.

That would allow access to a loose 1000 pounder sitting on the other door, without dropping it on the tarmac.

Nomex knickers on, awaiting flaming.

Sooty

[Ramshornvortex]

How many times have you or I dropped something when we've been working in the bomb bay - it always rolls to the lowest point, i.e. the rubber seals between the two doors....I haven't tried it personally, but I'm pretty sure that's what would happen to a 1,000 pounder! ;)

RHV

[sooty655]

The outer doors are sloped in the (possibly forlorn) hope that the loose banger will roll to the side. Even if it doesn't, access through the hatch would allow it to be secured. Then with one door open, a small crane could access it.


How many times have you or I dropped something when we've been working in the bomb bay - it always rolls to the lowest point


Dropped something? ME????:p

And how come your fingers were sticky with OM15 picking 2BA nuts out of the SIDE channel?

Nomex knickers still on.............

Sooty