full-pressure (i.e. a space suit) or partial-pressure?

[steve25]

Quick question from a civi lurker..
I am aware from visiting RAF Alconbury in the 80s/90s ( and later watching the James May documentary) that the TR1(U2) pilots wore full pressure (space suits) for high altitude flights. Did RAF pilots flying at similar altitudes have these suits, and if not, did that impact on the chances of their survival if they parted company with their aircraft?

[Pontius Navigator]

A question of height, pressure and time. IIRC, for flight over 40k for flight up to 50k you could use a mask alone with a Mk17 regulator delivering an overexposure of 30mms O2.
With a Mk21 you were limited to 45k on the mask alone.
If you wore a pressure jerkin you could again go to 50k but also received a greater partial pressure, 45mms I think.
If you added G- pants you could go to 56k and 70mm O2 over pressure. Beyond that it was a function of your neck, gullet, ears and tear ducts to hold a greater pressure. Therefore for flights to 66k a Taylor Partial Pressure helmet was worn. I don't know its pressure limit.

In the event of loss of pressure a rapid descent had to be initiated within 30 seconds and a rate of descent of at least 10k/minute to 40k.

In the event of a bailout your ROD would be much lower. I believe a Canberra crew was rejected by their aircraft at very high altitude, probably in 1960s and were reputed to have white hair when they eventually landed. Rumour had it that a photo flash ignited under the aircraft.

[newt]

Oh happy days! Just doing the course at North Luffenham was enough for me! Practicing pressure breathing for a week before an explosive decompression in the chamber! Total body abuse! I don’t ever recall flying with the partial pressure suit but assume I must have done it at the OCU! Glad I went to Germany where the flying was mostly low and medium level!

[Pontius Navigator]

I know some crews ignored the limits.

[Bigpants]

Drager made a lovely pressure hood for the pilots of the Horton 229 Flying Wing.

[scorpion63]

A question of height, pressure and time. IIRC, for flight over 40k for flight up to 50k you could use a mask alone with a Mk17 regulator delivering an overexposure of 30mms O2.
With a Mk21 you were limited to 45k on the mask alone.
If you wore a pressure jerkin you could again go to 50k but also received a greater partial pressure, 45mms I think.
If you added G- pants you could go to 56k and 70mm O2 over pressure. Beyond that it was a function of your neck, gullet, ears and tear ducts to hold a greater pressure. Therefore for flights to 66k a Taylor Partial Pressure helmet was worn. I don't know its pressure limit.

In the event of loss of pressure a rapid descent had to be initiated within 30 seconds and a rate of descent of at least 10k/minute to 40k.

In the event of a bailout your ROD would be much lower. I believe a Canberra crew was rejected by their aircraft at very high altitude, probably in 1960s and were reputed to have white hair when they eventually landed. Rumour had it that a photo flash ignited under the aircraft.
Is this the one you refer too?Canberra B. Mk.6 WT207, Monyash, Derbyshire ? Peak District Air Accident Research (http://www.peakdistrictaircrashes.co.uk/crash_sites/peak-district/english-electric-canberra-wt207-monyash/)
Canberra B. Mk.6 WT207, Monyash, Derbyshire ? Peak District Air Accident Research (http://www.peakdistrictaircrashes.co.uk/crash_sites/peak-district/english-electric-canberra-wt207-monyash/)

[air pig]

Drager made a lovely pressure hood for the pilots of the Horton 229 Flying Wing.


https://forum.warthunder.com/index.php?/topic/135017-draeger-pressure-suit-for-horten-ho-229/

[CharlieJuliet]

The decompressions were to 56k ft for partial pressure jerkin and g suits and 60 k ft plus a Taylor helmet. Without the helmet it was uncomfortable breathing against the oxygen pressure whereas with the helmet it was easy. For the lower 'bang' there was a doc with you. For the higher 'bang' you were left alone in the chamber with a doc outside. I remember the chamber misting up after the 60 k decompression and, after some seconds, seeing the doc looking in anxiously hoping to see a thumbs up otherwise he had to come in after you. We always flew with the pressure jerkin as there were not enough SARAH/SARBE (can't remember which) to out fit both a jerkin and a Mae West each. So the Boss wanted us to wear the jerkin in case we had to go high alt. Difficult at first but we got used to it.

[Pontius Navigator]

Scorpion, thank you. That is near enough to the story I heard some 6-7 years after the event. Is there any amplification on the crew bailout?

[steve25]

Thank you for all the replies. Just reading very informative Aero Society paper on history of flying clothing.

[scorpion63]

In conversation with Peter some years back he said he had no recollection of having ejected from the aircraft and was only aware after dropping several thousands of feet and was very cold, he suffered frost bite and bruising but no lasting effects and was a sprightly gentleman and a pleasure to meet.

[Pontius Navigator]

no recollection of having ejected from the aircraft and was only aware after dropping several thousands of feet and was very cold, bi
Hence my TiC that the aircraft rejected him rather than ejected.

On emergency oxygen, I know we didn't have a lot, 12 - 15 minutes IIRC. In the event of loss of presurisation we were told to descend at 10,000 ft per minute, ie a minute from 50k to 40k, but after a bailout and in free fall I expect 160 fps would have been obtainable but as you say, B-cold

[ACW418]

At North Luffenham in the mid 1960's the explosive decompression was from 27,000 feet to 52,000 feet for V Force crews. 27,000 because that was the highest the Vulcan pressurisation let you go and 52,000 because that was the official limit of the pressure breathing system using the Pressure Jerkin. On my squadron we always wore the Partial Pressure Jerkin but not the G Pants (we were never issued with them).

ACW

[Bigpants]

North Luffenham did something equally daft to Lightning crews. Cannot remember exactly, it was 1985 when I went through, but recall getting decompressed rapidly to a great height and then pressure breathing for a few minutes. Can I sue the MOD for this kind of thing? I was also subject to a mock ejection at North Luffenham in 1980 ish which really hurt my back for an few hours. Still, character building stuff as they used to say before Human Rights were invented.

[Pontius Navigator]

ACW, I was just ahead of you and we had the G-trousers and the privilege of a bang to 56k and without digging out my old log book I think it was 30 seconds. The following year, 65 and 66, it was as you say 52k and 15 seconds. The next in the phart chamber was for F4 'LL do only to 48k.

Bigpants, that was just one of the cruel and unusual tortures inflicted on our little pink (and later any coloured) bodies. One side effect of the bang was the appearance of little red spots on the skin with me today. Then there were the regular attempts drown drown us in freezing seas.

At least they let us wear denims and never thought to have us join the RM in the Arctic in case we landed bollock naked in a hole in the ice.

Luffenham had a Go however towing us on our backs across a snow covered airfield behind a 4-tonner. Having done that the instructor said now on your front. We declined. He then did it himself on his front. We were VERY impressed. When he said now you turn we again declined.

​His threats were hollow as they could no chop an entire course.

[Herod]

Hello all you , like me, "mature" gentlemen. I happened to be in the South Cerney area a few weeks back, and drove through the very des. res. area of the Cotswold Water Park. Nice houses and nice boats. i wonder if they are ever troubled by the ghosts of cadets, in denims and carrying ropes and scaffold poles, and rolling oil drums?

[Pontius Navigator]

Hello all you , like me, "mature" gentlemen. I happened to be in the South Cerney area a few weeks back, and drove through the very des. res. area of the Cotswold Water Park. Nice houses and nice boats. i wonder if they are ever troubled by the ghosts of cadets, in denims and carrying ropes and scaffold poles, and rolling oil drums?
Crossing lakes of nitric acid . ..

But nice deviation, you should be dipped in that green water.

[ACW418]

PN,

I went through North Luffenham in July 1964.

ACW

[Pontius Navigator]

PN,

I went through North Luffenham in July 1964.

ACW
I was just ahead of you and on the Sqn in June. The OCU was still coming to terms with the switch to low level and the new war plan only came in on 1 Jul. Our QFI had us do all the trips in full kit just in case.

And it might have been necessary when we deployed to FEAF.

[Pontius Navigator]

Just dug out my old log book, we were indeed banged to 56,000 ft and held there for 30 seconds before a 10k/m descent.

[CharlieJuliet]

Did the bang seat ride in '63 (seem to remember that the time delay of .5 sec before the seat fired seemed to last forever!!), and the 2 Lightning runs above in '65 and '66. But the Phantom run in '68 was to 56 k but only for 8 seconds as opposed to the Lightning runs which held the height for 30 seconds.

[Pontius Navigator]

CJ, I only had 48K in '69. There is no duration quoted just that we went from 22.5 to 48 in 3 seconds.

[nipva]

Being curious and also memory-challenged, I too have checked my logbook. I see that pre Gnat we did a rapid decompression to 48K and held for 30secs and pre Lightning the rapid decompression was from 27K to 56K in 3 secs but no record of the 'hold'. I assume though that it must have been for around 30secs so that we could practise our pressure breathing. A few years later I experienced a full pressurisation failure at 56K whilst carrying out an air test. Fortunately it was not of the explosive variety so I was already in a rapid descent by the time the pressurisation had failed completely and I remember at the time that I was not really aware of the pressure breathing - a healthy shot of adrenalin works wonders!.

[Chugalug2]

In a pathetic attempt to match the very big numbers being quoted here from various logbooks I consulted mine (ex Hercs). I really shouldn't have, but at least it shows the vast range that North Luffenham dealt in.

"March 1968 ASC Aviation Med Course, Rendered Hypoxic R/D 8K-35K/30 secs-Satis."

Grow Bags sufficed!

[flying brain]

[QUOTE=Pontius Navigator;10198670]Hence my TiC that the aircraft rejected him rather than ejected.

I have the Martin Baker ejection seat firing cartridges from this accident and they were both fired, so crew ejected.

[Pontius Navigator]

[QUOTE=Pontius Navigator;10198670]Hence my TiC that the aircraft rejected him rather than ejected.

I have the Martin Baker ejection seat firing cartridges from this accident and they were both fired, so crew ejected.
TiC = Tongue in Cheek

[oldmansquipper]

I recall doing preflight checks with Vulcan crews at Waddo in the mid 60s when the maximum number of PB 'toggle downs' was, I think, 3. If an effective seal could not be achieved and the white dolls eye on the Godfrey Test Cab stayed on, the crew member could not fly that day.

Perish the thought that certain aircrew deliberately manipulated this so that so that they didn't have to fly. It's what we flying clothing types were there for - It would be our fault of course.

[Percy Cute]

For the benefit of steve25:
https://cimg6.ibsrv.net/gimg/pprune.org-vbulletin/750x443/taylor_helmet_74752b5ed2ef810291963328dbd8e3c03c8084c4.jpg
By the by, staff at the OCU air-testing the Mk1 and 1a would normally wear the jerkin but I don't remember what they wore for Mk3 air tests. All the UK Lightning stations had jerkins at least until the mid 70s when most of the Lightning squadrons were disbanded. The helmets were long gone by then and the Pilot's Notes said that the aircraft "should not be flown above 60,000ft" (no mention of prohibition). Hence this was largely ignored, allegedly. I'm told.