Go Back  PPRuNe Forums > Flight Deck Forums > Tech Log
Reload this Page >

NEMP protection - ACJ and BBJ Considerations

Wikiposts
Search
Tech Log The very best in practical technical discussion on the web

NEMP protection - ACJ and BBJ Considerations

Thread Tools
 
Search this Thread
 
Old 28th May 2006, 12:59
  #1 (permalink)  
Thread Starter
 
Join Date: May 2006
Location: uk
Posts: 13
Likes: 0
Received 0 Likes on 0 Posts
NEMP protection - ACJ and BBJ Considerations

I understand that the A320 series has no NEMP (nuclear electromagnetic pulse) or DEW (direct energy weapon) protection as part of its design criteria.

With the world becoming more dangerous, the possability must surely exist that one day an aircraft could be affected by NEMP or DEW.

With traditional aircraft such as B737, a total electrical and hydraulic failure will not render aircraft uncontrollable. (manual reversion)

With fly-by-wire, and say all circuits fried by NEMP or DEW, what will happen? I understand the RAT may deploy from batt bus, but if this system has no NEMP/DEW in the design criteria...will it deploy and will aircraft be controllable? Are their any circuit boards in the RAT deployment system?

A high altitude nuclear explosion can send a NEMP 2500 km!

I have let this thread get a little out of hand and am now in the process of bringing it back into line. Some of the posts I will delete, others I will amend without comment.

Please, ladies and gentlemen, can we adopt a reasonable degree of decorum in this forum .. the original question is as valid as any other and deserving of reasoned comment.

EMI considerations are not the stuff of imagination but are addressed at the design and certification stage. Perhaps the nuclear catastrophe scenario is a little out of left field .. but is it not an interesting question to contemplate ?

.. even contemplating a 73 with no hydraulics at all and no electrics is the stuff of nightmares ... rather anyone else than me, I'm afraid

Last edited by mach 4.0; 28th May 2006 at 22:14.
mach 4.0 is offline  
Old 28th May 2006, 15:12
  #2 (permalink)  
Warning Toxic!
Disgusted of Tunbridge
 
Join Date: Jan 2005
Location: Hampshire, UK
Posts: 4,011
Likes: 0
Received 0 Likes on 0 Posts
What makes you think a 737 or indeed ANY other lane will be immune to the effects. Apart from taking out every car, aeroplanes would be affected with fried electronic fuel control units and every other control system. I think it's questionable whether there are any aeroplanes not hardened that will survive. Not really a problem, there is unlikely to be much to come down to. Good on Airbus not to bother!
Rainboe is offline  
Old 28th May 2006, 15:32
  #3 (permalink)  
Thread Starter
 
Join Date: May 2006
Location: uk
Posts: 13
Likes: 0
Received 0 Likes on 0 Posts
This is a serious question and I would be interested to find out the answer.

FYI if the 737 lost all power, it could glide in manual reversion.

Whats wrong with considering the effect of the electromagnetic environment you are flying in?

Electromagnetic interactions form a fundamental part of the survivability of picture of todays modern aircraft.

Electronic warfare, the digital battlefield does exist.

Rainbow, A DEW or NEMP would not necessarily mean "there is unlikely to be much to come down to"

Clandestino, ok lets say its impossible for a terrorist activity to result in a NEMP or DEW, what about an accident?

IF you do not have the info or are not interested, thats fine, dont bother replying. But I do not believe in denying others to chance to expand their knowledge.

It is possible for a DEW to be directed at an aircraft. They can be designed for this purpose.

Say you were going to fly an ACJ for a head of state, wouldn't it be nice to know the effect of a DEW?

Last edited by mach 4.0; 28th May 2006 at 15:54.
mach 4.0 is offline  
Old 28th May 2006, 15:46
  #4 (permalink)  
 
Join Date: Mar 2005
Location: England
Posts: 730
Likes: 0
Received 0 Likes on 0 Posts
Hi,
The 'bus doesn't have manual reversion but it does have manual control of both the rudder and THS in the event of total electical and hydraulic failure.
Fargoo
Fargoo is offline  
Old 28th May 2006, 15:52
  #5 (permalink)  
 
Join Date: Jun 2004
Location: UK
Posts: 172
Likes: 0
Received 0 Likes on 0 Posts
Mach 4,

I think you may find the A320 was designed and certified as a civilian aircraft, not really intended for war zones.

Probably not much about directed energy weapons in CS25 or EUROCAE ED14.
Rivet gun is offline  
Old 28th May 2006, 16:00
  #6 (permalink)  
Thread Starter
 
Join Date: May 2006
Location: uk
Posts: 13
Likes: 0
Received 0 Likes on 0 Posts
fargoo, thanks. The question is is there any circuitary in the RAT system? If so it could be fried by NEMP or DEW.

Another airbus deploys the RAT by cable (perhaps A330 but not sure)

Rivet gun, if you do not know the answer fine, thanks for your input.

To save anyone repeating that its unliley to happen, etc etc. I agree its unlikely to happen.

But I am still interested in the answer?
mach 4.0 is offline  
Old 28th May 2006, 16:49
  #7 (permalink)  
 
Join Date: Dec 2004
Location: Andalucia
Posts: 728
Received 0 Likes on 0 Posts
Depends what you mean by circuitry really, if you mean switches, solenoids, and wires supplied from the Hot Battery Bus then the answer is yes.
If you mean solid state electronics then the answer is no.
Wodrick is offline  
Old 28th May 2006, 17:14
  #8 (permalink)  
Warning Toxic!
Disgusted of Tunbridge
 
Join Date: Jan 2005
Location: Hampshire, UK
Posts: 4,011
Likes: 0
Received 0 Likes on 0 Posts
Look, you are asking a hypothetical question. Every electrical circuit will get fried. All electronic control units will be burnt out, all navigation and instrumentation will probably be worthless. What exactly more do you want to know? Why passenger aeroplanes aren't shielded with hundreds of kilos of lead each? I think Airbus and Boeing have quite reasonably taken the view that you can only defend an aeroplane from direct attack in this manner to a limited degree.
Rainboe is offline  
Old 28th May 2006, 20:54
  #9 (permalink)  
 
Join Date: Feb 2005
Location: Correr es mi destino por no llevar papel
Posts: 1,422
Received 1 Like on 1 Post
Rainboe/ Clan Just because you do not have the technical knowledge
Now that's a brave one! Even If I didn't have technical knowledge, I could simply use encarta or wikipedia or whatever to fill in the gaps and guess what wiki says about DEWs - they are either fictional or don't work as planned which is what I knew before. Only serious DEW project, US YBL-1 is seriously stuck in the development phase. And if that moneywaster is ever operative as planned, its laser won't just be able to fry your circuits but your airframe as well, be it B737 or A320.

Whats wrong with considering the effect of the electromagnetic environment you are flying in?
Nothing, but no one has ever intended, or intends, to fly a transport category airplane into nuclear warzone or into crossfire between Flash Gordon and Evil Ming Empire, the only warring parties currently equipped with DEWs.

Rivet gun, if you do not know the answer fine, thanks for your input.
Rivet Gun certainly knows the answer and he tried to tell it to you by using mild irony.

But I am still interested in the answer?
And the question was: Is A320 inability to take major trashing from nuclear explosion design flaw?

And the 1 eurocent answer is: NO !

This thread is based on very false assumption that FBW airplane falls out of the sky when its electronics are burnt and "classic" flies happily on. Mach 4, if you were really 737 rated, you would have known that manual reversion is not a joke and manual reversion with absolutely no electrics is certain killer. So if you get hit by Flash Gordon's death ray you'll meet your maker very soon, not much difference between classic controls and FBW.

Not much chance of it happening in real life, though. Phew!
Clandestino is offline  
Old 28th May 2006, 21:01
  #10 (permalink)  
Thread Starter
 
Join Date: May 2006
Location: uk
Posts: 13
Likes: 0
Received 0 Likes on 0 Posts
Woodrick,

thanks for your reply

The question relates to will the aircraft loose all flight controls in event of NEMP or DEW event? and in particular will the RAT deploy and will some flight controls work. ACJ's are becoming more and more popular and there is a possability I may fly one in 2007/2008. The principal I currently fly for is looking at electronic counter measures for his aircraft and the question of NEMP/DEW has arisen. He pays alot of money for his aviation department and his questions to me need to be answered fully. If I gave answers along the lines of postings above, I would be considered a schoolboy and probably fired!

I am awaiting an answer from the head of A320 technical team, but in the meantime I am interested if anyone reading this forum has specific knowledge.

Rainboe,

If you are not interested in the answer to this question fine, but I am! A B737 can glide in manual reversion, lower undercarriage and has a chance to survive. And yes I have done this in simulator and provided you remain vmc it is not that difficult, at least you have a chance.

Someone on this forum may have the technical knowledge I am interested in. if you have not or are not interested - why are you posting? I respectively ask you to only post if you can add to this request.

This forum can be really useful in increasing knowledge, and knowledge is a good thing which should not be censored.

PS if someone wants to discuss airbridges, let them. If you are not interested you do not have to read the post!

Clandestino,

same to you, if you do not know the answer or are not interested...fine, but why the hostility? I do not have any false assumptions about FBW and whether they "fall out the sky", I simply do not know. I have not done an airbus course, and if I did I may not have that knowledge anyway. I am merely seeking an answer to my question. Look its not a big deal if you cannot help, please don't bother replying if you cannot add something positive. I really do not want to argue about whether or not I should be asking this question. I am asking the question and nothing you say will stop me from seeking the answer.

Thank you

Last edited by mach 4.0; 28th May 2006 at 21:22.
mach 4.0 is offline  
Old 28th May 2006, 21:12
  #11 (permalink)  
 
Join Date: Oct 2004
Location: UK
Age: 51
Posts: 171
Likes: 0
Received 0 Likes on 0 Posts
Sorted.

Originally Posted by mach 4.0
Woodrick,

thanks for your reply

The question relates to will the aircraft loose all flight controls in event of NEMP or DEW event? and in particular will the RAT deploy and will some flight controls work.

Rainboe,

If you are not interested in the answer to this question fine, but I am! A B737 can glide in manual reversion, lower undercarriage and has a chance to survive.

Someone on this forum may have the technical knowledge I am interested in. if you have not or are not interested - why are you posting? I respectively ask you to only post if you can add to this request.

This forum can be really useful in increasing knowledge, and knowledge is a good thing which should not be censored.

PS if someone wants to discuss airbridges, let them. If you are not interested you do not have to read the post!
Reading the above, I have an answer for you.

The Airbus will crash
The 737 will not ( possibly )
You want to fly on 737's.
You do not want to fly on A320's.
You most certainly do want to avoid flying in nuclear war zones.
There are ( currently ) ZERO nuclear war zones on the planet.
Flightman is offline  
Old 28th May 2006, 21:38
  #12 (permalink)  
Thread Starter
 
Join Date: May 2006
Location: uk
Posts: 13
Likes: 0
Received 0 Likes on 0 Posts
Hello Flightman --manager at LHR

Thanks for taking the time to reply.

Obviously your answer that airbus will crash and boeing will not is not the technical answer I am looking for. I am sure my principal would be impressed if I repeat what some manager at LHR thinks without any technical explanation.

If someone really does have something sensible to add it would be interesting.
mach 4.0 is offline  
Old 28th May 2006, 21:46
  #13 (permalink)  
 
Join Date: Feb 2005
Location: Correr es mi destino por no llevar papel
Posts: 1,422
Received 1 Like on 1 Post
Bringin' obstinacy to new levels...

Let's assume we have two airplanes, 737 and A320, and there is sudden nuclear explosion at place relativelly close and equidistant from each of the planes.

A320 gets his FBW fried and spins out of the skies uncontrollably.

B737 gets his electrics fried and yes, it can glide, and yes it can lower its gear and yes, there's manual reversion but WHERE THE HECK WILL YOU BE GOING NOW IN 737 WITH NO AHRS, NO ADC AND NO STBY INSTRUMENTS EITHER (it's all solid state nowadays)?!?!?

Short answer - earthwards, rapidly.
Clandestino is offline  
Old 28th May 2006, 21:54
  #14 (permalink)  
Thread Starter
 
Join Date: May 2006
Location: uk
Posts: 13
Likes: 0
Received 0 Likes on 0 Posts
Ok clandestino

Thats a bit better!

But are you certain" airbus will spin out of sky uncontrollably"

Airbus have already said they could add an option for the RAT to be manually deployed by cable from flight deck. (in the same way as another airbus, think they said A330 but not sure)

Assuming RAT deploys either manually by cable or by the standard automatic deployment, are you saying airbus will definately "spin out of sky" and if so can you back this up with any technical opinion.

I wouldn't be so sure that NEMP/DEW will never be a factor for civilian aircraft. For example, Iran recently made threats in Israel's direction. Never say never! who knows whats is in store for the world in the next few years.

FYI with 10,000 hours and 20 years flying experience, I think on a good day with a bit of luck i could pull off a double engine failure in the situation you describe. But at least the possibility of survival exists!

Thank you

Last edited by mach 4.0; 28th May 2006 at 22:22.
mach 4.0 is offline  
Old 29th May 2006, 11:06
  #15 (permalink)  
 
Join Date: Nov 2002
Location: Heart of Europe
Posts: 198
Likes: 0
Received 0 Likes on 0 Posts
1.) Aircraft do not have "unprotected" circuitry or every single lightning strike would fry our equipment. So it may not damage all equipment.

2.) Energy density is required to induce an electric field. The further away the lesser the problem. If you are close enough to have the circuitry fried your probably close enough not to have to bother for a landing anymore.

Try this:

http://www.qsl.net/n9zia/emp.html

more coming up when I can find it again.
error_401 is offline  
Old 29th May 2006, 11:23
  #16 (permalink)  
 
Join Date: Apr 2006
Location: Ho Chi Minh City Vietnam
Posts: 37
Likes: 0
Received 0 Likes on 0 Posts
EMP

error_401,

Are you a Ham radio operator?

WA3IKQ
TomConard is offline  
Old 29th May 2006, 11:27
  #17 (permalink)  
 
Join Date: Jul 2001
Location: planet earth
Posts: 451
Likes: 0
Received 0 Likes on 0 Posts
Wow what a thread !!

If your boss is that worried about getting fired by a nuke, then I suggest you get a new boss !! Also, if you are figuring to get your jet EMP hardened, then you had best suggest he either:

a. Get some serious money to do the work (even the majority of mil jets will fall out the sky post nuclear event)

b. Go the other way and buy an un-refirbished DC3 (or equivalent). Even then, I think the compass would not be much use.

PS. As we are on an A320 thing, does anybody know the best cattle class seats on BA's 320's ? Got to fly in one soon, just hope I make it.....

c130jbloke is offline  
Old 29th May 2006, 11:31
  #18 (permalink)  
 
Join Date: Nov 2002
Location: Heart of Europe
Posts: 198
Likes: 0
Received 0 Likes on 0 Posts
c130jbloke

I suggest to move the thread to the jet blast and asking for ideas on how to harden aircraft against NEMP. Should be fun.

Don't you think that the DC3 could be in danger of blowing the fuel in the tanks? This could be an additional threat.

P.S. sorry forgot about the seating in an A320. I don't know BA's cabin layout but overwing exit row is a good guess. Usually slightly longer pitch between the seats. Front and aft exits are usually behind separation walls so of no use. Don't sit in the last row usually the seats do not allow for full travel back to relax position.
error_401 is offline  
Old 29th May 2006, 11:36
  #19 (permalink)  
Warning Toxic!
Disgusted of Tunbridge
 
Join Date: Jan 2005
Location: Hampshire, UK
Posts: 4,011
Likes: 0
Received 0 Likes on 0 Posts
Look chum, I'm rated on the 737 (as well as the 747-400), and shortly will be re-rated on it. I do happen to know what I'm talking about. I'm glad you are so glibly confident a 737 would survive manual reversion- I am not so sure it is that assured. All instruments are supplied by the Air Data Computer, so they would go out. The Standby ASI is supplied with direct pitot static, so hopefully that would work, but not necessarily if the standby electrical system was burnt out.

You harp on about RATs. They would have electrical control systems that may be burnt out, so probably useless.

You seem to have a bee in your bonnet about this. Can you advise me how many aeroplanes have ever had a problem due to EMP interference, and how much of a hazard you actually think it currently is to civil aviation? Do you think perhaps we could better invest in protecting aeroplanes from meteor strikes, for instance, or beef up the undercarriages so if an earthquake occured during the take-off/landing rolls, we would be better protected from disaster?

So you are writing to people demanding better protection from a hazard that:
*hasn't ever occured yet
*there is no likely prospect of it occuring yet.
Rainboe is offline  
Old 29th May 2006, 11:43
  #20 (permalink)  
 
Join Date: Jul 2001
Location: planet earth
Posts: 451
Likes: 0
Received 0 Likes on 0 Posts
E401,

Noted, thanks for the A320 tip. I figure that would be problem with the Nuke vs aircraft problem, its such a useful weapon for ending the world......

I still got to fly in that A320 though......bugger.

c130jbloke is offline  


Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.