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Distant Voice
30th Jul 2009, 20:13
After several variations for engine start-up on Nimrod aircraft, following the incident involving XV249, can someone enlighten me as what is the current procedure (from Start APU, X-feed open to all engines running, X-feed closed)?

DV

Distant Voice
31st Jul 2009, 16:28
Dear jimgriff,

Why do you find it necessary to make a stupid comment with regards to a genuine question? I know the sequence is 3,4,2,1, I would simply like to know what power settings were finally agreed on at each stage, following the XV249 incident. Perhaps I should have made my original statement more clear.

By the way, I do not understand the term "beadwindow"

DV

VinRouge
31st Jul 2009, 16:39
If you needed to know you woud know.

This thread needs closing. Unless you also want the nuclear access codes to go with your nimrod request?

Squirrel 41
31st Jul 2009, 16:51
DV,

Why do you think you need to know? If you did, you would; or you'd be told.

Mods, Vin Rogue is right; can we close this one down, pls.

S41

Distant Voice
31st Jul 2009, 16:51
VinRouge:

I have got the "access codes", I was just asking about the Nimrod start sequence, which I assume has been adjusted following UTI/NIM/051 and 50.

Is that what you have been telling Charles H-C "If you need to know, you would know"?

DV

Distant Voice
31st Jul 2009, 17:37
S41 and VinRouge;

What I ask for is not a threat to national security.

Having just scanned all your previous postings, I suspect that you are not Nimrod people.

I await a reply from an informed Nimrod ground or flight engineer.

DV

anita gofradump
31st Jul 2009, 17:37
Why don't you try to get the info you want under the FoI? It seems to have been successful for you to date. And it'll be a lot more 'legit'........if they decide to give it to you.

Try not to bite so hard.

GOLF_BRAVO_ZULU
31st Jul 2009, 18:47
Regrettably, Pontius Navigator’s Thread on Beadwindow appears to have disappeared. Anyway which EEFI is Distant Voice in danger of compromising?

enginesuck
31st Jul 2009, 18:59
We dont use x feeds to start anymore, Rolls Royce have developed a kick start mechanism. I hope this helps

Distant Voice
31st Jul 2009, 19:39
Thank you Enginesucks

DV

EdSett100
31st Jul 2009, 19:46
The BOI report describes Nimrod systems and their operation in some detail and the Inquest was held in open court. Therefore it is churlish to deny DV this basic info on the basis that it is either sensitive or a risk to national security. To some degree it is in the MOD's interest to let him and other interested parties know what we are doing. By doing so, we would obviate an unnecessary response to a FOI request, at best, or be accused of hiding information, at worst.

DV, here is your answer:

The Release to Service prohibits anyone from opening the crossfeed valves in flight. It also prohibits the opening of the crossfeed valves on the ground when any engine is running above 80%. This limit does not change the well established (and safe) engine start procedures in use since all Mks of Nimrod entered service. The limitation only affects some start fault diagnosis techniques. We initially start the APU which then supplies the air, through the crossfeed duct to No 3 engine. Provided that the area behind No 3 engine is clear for it to be accelerated, the APU will then be shut down and the No 3 engine will be set to 75%, normally. If air conditioning is required in the cabin due to high temperatures, the No 3 will be set to 80% and cabin air will be switched on. The No 3 engine then supplies the air to start the other 3 engines in sequence: 4, 2 then 1. Once they are all started, the crossfeed valves are closed and the No 3 engine is set to idle RPM (52%). Simple and safe.

Regards
Ed Sett

Distant Voice
31st Jul 2009, 21:28
EdSett100:

We have had some "ups and downs" over the past couple of years, but I must say a big thank you for coming to the rescue. I was hoping that you would show up and inject a meaningful explaination, which you have done.

Is there any truth in the comment made by enginsucks? I understand that AEDIT was tasked to investigate the feasibility of starting engines without bleed air into the X-feed duct, but the last I heard the task was still ongoing.

Once again, many thanks.

DV

Flap62
31st Jul 2009, 21:35
A quick question for jimgriff and VR,

How in any way did Ed Sett's answer compromise security?

I often find that people on this site type "beadwindow" to hint that they know more than others - "if you needed to know, you would" type of stuff. Pathetic.

Squirrel 41
31st Jul 2009, 21:55
EdSett, DV et al

Many thanks for answering DV's question. My concern was two fold (i) that the information was not in the public domain, and (ii) that given the sometimes sensational press coverage of Nimrod safety issues after the crash of 230, that this could - and not by DV - lead to more of it. I am happy to stand corrected.

S41

Distant Voice
1st Aug 2009, 05:56
Thanks S41

DV