View Full Version : Sustained +9G....
BEagle
5th Nov 2012, 20:40
I've just seen a pretty amazing demonstration of a new German anti-G suit on Richard Hammond's Miracles of Nature (BBC1). The subject coped with a sustained +9G - his party trick was to solve a Rubik's cube whilst at +9G!
+7 or +8 for a few seconds only was about all our Gnat/Hunter/Hawk kit could cope with - does the RAF have a similar piece of +9G kit for the Typhoon?
Even so, surely would you need constant practice to be able to cope with the full system capability? But with today's bean counters, is that feasible?
Courtney, mon brave, how often did you take the F-15C to its limit? Rather more often than we did in our creaking old Charlie fit F-4s, I would venture....
Treble one
5th Nov 2012, 20:48
I believe that the anti G kit on the Typhoon was specially develloped, with a specially designed anti G jacket and full length 'bladders' in the trousers, rather than the usual G trousers which have not got full coverage.
I read an article where a Typhoon pilot (I think it was this years display pilot Sqd Ldr McLoughlan) said that the kit was so good, they could sustain high G longer, and it felt that it was 'less' G than it really was.
I am sure a more qualified member of the forum will be able to give you more details.
I think the first job when you are heading off to the Typhoon OCU is to have a trip to North Luffenham to get fitted up for your special G kit (I think that was in a different article).
Courtney Mil
5th Nov 2012, 20:54
Yes, been watching that too, BEags. Very interesting. We taught our F-15 students to operate the jet at 9g. Not for 5 seconds, for the whole fight, which admittedly would be descending and would eventually reach base height. Then you can't descend so it all slows down and the g reduces. But that was sustained 9g. And not just sitting up straight, but twisted round looking out the back in the case of Defensive BFM.
In fairness the Hamster missed out the bit about wearing an ordinary g-suit and a well-trained straining manoeuvre. 9g isn't the best place in the world to sit, just for fun. I did it the USAF's centrifuge and hated it. But it's quite do-able in the jet.
Courtney Mil
5th Nov 2012, 20:56
And, yes, the full g-suit (combat-edge to the Americans) plus pressure breathing is a big step forward.
BEagle
5th Nov 2012, 21:00
But it's quite do-able in the jet.
No doubt a reduced heart-to-brain height helps, eh Courtney....;)
+8G was also quite do-able in the Hunter T7 as I once proved....OOPS! :uhoh: But heaven knows how much Fiennesy pulled avoiding the North Sea in a 90 deg dive one night in his Lightning!
G tolerance reduces without practice though - as we usually found out on Day 1 at ACMI....:rolleyes:
Courtney Mil
5th Nov 2012, 21:03
Two things in my favour that really deos seem to help: the reduced heart-brain distance and all that hard work at getting the arteries nice and hard.
I believe that the anti G kit on the Typhoon was specially develloped, with a specially designed anti G jacket and full length 'bladders' in the trousers, rather than the usual G trousers which have not got full coverage.
I haven't seen the documentary (here in Germany we don't have BBC) but I assume they are talking about the 'Libelle' suit. That was an originally swiss development which was adopted by the GAF to better cope with the 9g of the Typhoon.
The main trick of that suit was that it is liquid filled in many small capillaries instead of using air pressure.
Liquid has pretty much the same density as human blood, so the the centrifugal force of the liquid equalises the increasing pressure of the blood in the lower parts.
I think I read that meanwhile the USAF has adopted the same concept for the Raptor pilots but I'm not 100% sure.
BEagle
5th Nov 2012, 21:07
Funny thing was, at Chiv, old age and treachery in a base height brawl often beat the young racing snakes. All down to a bit more experience of pulling G, rather than fitness and skill.
Tashengurt
5th Nov 2012, 23:08
My last posting was working on the development kit being tested at Farnborough. Back then the Typhoon was the EF2000 and the kit comprised Full Coverage Anti G Trousers, commonly known as FCAGTS or faggots, socks which attached to these and a pressure vest built into the LSJ. I don't know how many of these bits got past that stage.
BEagle
6th Nov 2012, 07:29
No, not the Libelle suit, but a 'Giraffe' suit. Invented by a Swiss designer at the German Air Force Institute of Aviation Medicine, it is a one-piece suit which uses air, not liquid.
See BBC iPlayer - Richard Hammond's Miracles of Nature: Super-Bodies (http://www.bbc.co.uk/iplayer/episode/b01nvn2n/Richard_Hammonds_Miracles_of_Nature_SuperBodies/) from 16:07 onwards - clip is about 14 min.
Having struggled with filming at 4-5g, I was impressed that he could lift the cube at 9g, let alone solve it!
I had the pleasure of flying in a Belgian F16 some years ago and was invited to earn my 9G pin by sustaining 9G+ for more than 30 Sec. A spiral descent in full burner did the trick, but it was a challenge to do anything more than a constrained lookout and monitor the G in the HUD with just a pair of G-pants for that amount of time.
Tash - I also took part in the Typhoon AEA testing at Farnborough doing sustained 10G in the centrifuge. The kit and pressure breathing made it quite easy to do the basics.
Just the thought of looking over my shoulder at 9g gives me a stiff neck, let alone doing a Rubik's cube.......................:eek:
dead_pan
6th Nov 2012, 12:41
...the thought of completing a Rubik's cube gives me a headache, let alone pulling 9g.
Lightning5
6th Nov 2012, 16:53
I am sure that Mr Fiennes did well that night. Although memory is slipping it was quite high. G meter in the cockpit , I think went up to 9 G , so this was on the stop, and the fatigue meter was reading 10 G. It was leaking fuel well on taxi in !!
No, not the Libelle suit, but a 'Giraffe' suit. Invented by a Swiss designer at the German Air Force Institute of Aviation Medicine, it is a one-piece suit which uses air, not liquid.
See BBC iPlayer - Richard Hammond's Miracles of Nature: Super-Bodies (http://www.bbc.co.uk/iplayer/episode/b01nvn2n/Richard_Hammonds_Miracles_of_Nature_SuperBodies/) from 16:07 onwards - clip is about 14 min.
Giraffe suit?
I've never heard of that !? Any Idea from which manufacturer it is?
The GAF uses Libelle from Autoflug (http://www.autoflug.com/) GmbH. That was a design originally developed by Swiss company Life Support Systems (http://www.lssag.ch/) AG[/URL] (by Andreas Reinhard) and now also sold via Swiss-German Autoflug.
Early Comparison:
[URL]http://www.safeeurope.co.uk/media/2767/ola%20eiken.pdf (http://en.wikipedia.org/w/index.php?title=Life_Support_Systems_AG&action=edit&redlink=1)
The following Link points to the two different anti g systems used by the different Typhoon users: FCAGTS (air pressure based) and Libelle (Liquid based):
Flightgear On-Line, the website for the collector of military flightgear (http://www.flightgear.dk/eurofight.htm)
Courtney Mil
6th Nov 2012, 18:39
Check out the BBC iPlayer for the explanation about the Giraffe thing. It is very interesting. There are a few bits missing from the science there, but pretty good none the less.
Check out the BBC iPlayer for the explanation about the Giraffe thing. It is very interesting. There are a few bits missing from the science there, but pretty good none the less.
I'll try that. I received a hint how I might be able to watch that where I am. Normally it is blocked outside UK.
I didn't understand the giraffe analogy at all - did I miss something?
Anyway, not a problem Mr Hammond would have;) I do envy him the ability to feel comfortable in an Elise.
That Libelle principle seems interestingly logical and so obvious that I'm astonished it hadn't been used before.
rightbank
7th Nov 2012, 07:03
Normally it is blocked outside UK
Try Expat Shield (http://www.expatshield.com/)
It gives you a UK IP address and enables you to watch BBC iPlayer outside the UK.
Works on a PC, not sure about iPads etc.
teeteringhead
7th Nov 2012, 13:13
I didn't understand the giraffe analogy at all ... maybe because ISTR giraffes have some amazing built-in kit that assists/maintains blood flow at the extremes of the "neck envelope"
On simple hydraulics, giraffes should:
a. Black out with head max up
AND/OR
b. Suffer "exploding head syndrome" with head max down
Clearly they do neither ....... must try and remember where I saw how they do that.....
[edited to add:]
Found a good and simple explanation here. (http://www.giraffeconservation.org/giraffe_facts.php?pgid=2) Includes the following: Giraffe, however, have a very tight sheath of thick skin over their lower limbs which maintains high extravascular pressure in exactly the same way as a pilot's g-suit.
.. it also seems that "Creationists" use it as evidence for "intelligent design" ......:8