Once again, many thanks to Taz, Bob, Mark and indeed all for the comments & insights. Fabulous stuff! Cheers, Ian
That is what is so cool about this forum and the people on it. Those of you who served are all my heroes. Risking your lives and pushing the limits of man and machine. Thank you.
On a return trip to Korea from Singapore, our entire flight of six Vipers topped off from the tanker for a planned Mach run at "50K" while still over water but within gliding range of Pusan...just in case something mysterious happened at 50K, as we were not supposed to go above that altitude without a pressure suit or our bodies would explode if our engine quit. Needless to say we all wanted to accidently overshoot 50K during the zoom climb by a little more than the other guys in the flight. Some of us overshot by quite a bit more than I can admit to without going to jail or seeming to be just plain stupid. Fortunately none of our engines quit and none of us exploded either!
FL470 in a Falcon 50 many years ago, near the end of a long flight. We were getting over some weather.
If we're realyl light we usually don't go any higher than FL400 in the C-5 (B, not a re-engined M model) even though the plane could go a little higher. Some planes have trouble holding pressurization any higher. It is a combination of not much bleed air at that altitude, and leaky seals (the ones on the front and rear cargo doors). The problem is worse with the old A models from what I've heard, but usually stuffing a wet blanket or trash bag where the leak is will help. I imagine that the M models have better pressurization due to their fancy 1980's technology engines. If we're really heavy and the temp dev sucks then we're still in the 20's.
You win. That's cool too. Foothills outside Denver, ~7300'. Incidentally, where all the pilots live. -F
Except hard to be a seaplane pilot in CO.. statewide ban for all waterways Colorado Advocacy - Seaplane Pilots Association
Not sure how popular seaplanes are in a land locked state, surrounded by mountains, where most (99%) of the lakes are man made and used as drinking water reservoirs. No, I was talking about commercial pilots. -F
The highest I have been...alone...4,500' on my two Solo Cross Countries!! Here are a couple of pictures. Oh, yeah, I'm a student pilot <G>. Image Unavailable, Please Login Image Unavailable, Please Login
Jim- The number is closer to 50,000', hence the AF reg. Partial pressure suits push that up to about 60,000' for the F-22 and the U-2 pilots wear full pressure suits for flights to who knows where. Same for the SR-71s when they were flying. For the F-22s, if you lose cabin pressure at FL600, time for a rapid descent.
Highest 50k or so, Concorde flight. I was 14 so don't remember much. I did buy the plastic models they sell in the inflight catalog. Cool keepsake to have. Coolest civilian. In the 90's my Dad wanted to upgrade up from his Piper Saratoga into a TBM 700. So we took one for a test flight. We got up to around 27k feet. The Socata test pilot demonstrated an emergency decent due to cabin pressure loss. That was pretty fun.
I was really kidding about he mysterious aspect of going above 50K in the Viper. It flies just fine above that. There are really two altitudes of concern that are getting confused with one another. The most serious from a traumatic point of view is that where blood will boil at body temperature...known as Armstrong's line. That varies somewhat depending on cardiovascular fitness, but generally it is 59-60,000 feet. Above this altitude serious barotrauma occurs in the unprotected body. The second altitude of concern is that where the partial pressure of oxygen at the alveoli in the lungs matches the partial pressure of oxygen in the blood where the concentration of oxygen in the lungs is 100%. Above said altitude, no oxygen will flow from lungs to the blood even when respiring 100% oxygen, resulting in hypoxia at a rate that varies greatly from individual to individual, but is never the less life threatening to all. This altitude is 49-50,000 feet and is the basis for the limits set on most conventionally-suited military fliers by regulation. When a cockpit depressurizes at 50,000 feet the time of useful consciousness is between 6-9 seconds. The TUC is generally halved in the setting of a rapid decompression. I had the sad responsibility for briefing the Phoenix press corps regarding all of this as the Payne Stewart mishap was unfolding back in '99.
Sitting at 7120 ft right now at a friend's house in Los Alamos, NM. Earlier today, I did a solo cross country in a C-172 between SAF and SLV and went to 12700. Highest I have ever been was in a Concorde that my parents paid for me to go on at Air/Space America '88 at Brown Field near San Diego.
Will- Even if you lose cabin pressure, it takes a while to bleed down, especially to the point where cockpit pressure equals outside ambient pressure. Always a good idea to descend at that point. We had an indication of a fuselage fire in an F-111F at mach 1.6 and FL400 during a Daytex air defense exercise over France. I dutifully turned off the air source and poof, just like you hear, the cockpit filled full of snow. Gone in a flash, but still really fun to see. Almost ended up getting married in Reims-Champagne that night, which would have really chapped off my wife.
Spent an hour in an open wicker basket at 18,000' MSL. No O2. Flight was from Gstaad, CH to Veneria, IT. Hour to climb and an hour to descend; 90 miles XC. Somewhere out there was the Matterhorn. From above it all looks like peaks of meringue. One of my more interesting logbook entries. Image Unavailable, Please Login
