Ptrjong From Netherlands, joined Mar 2005, 3768 posts, RR: 20 Reply 2, posted (6 years 7 months 1 week 5 days 2 hours ago) and read 11395 times:
Well. As far as I know, the F-16 still uses hydrazine as emergency fuel and it's dangerous stuff apparently. In the old days, whenever a Dutch F-16 crashed there was talk of the hydrazine. You don't hear much of it now, but I guess it would still be a matter of concern.
Peter
The only difference between me and a madman is that I am not mad (Salvador Dali)
GrandTheftAero From United States of America, joined Nov 2003, 254 posts, RR: 5 Reply 3, posted (6 years 7 months 1 week 5 days 1 hour ago) and read 11386 times:
Wow... I had no idea there was hydrazine on the F-16.
It's usually used as monopropellant for rocket thrusters and is also found on the Space Shuttle APU. It's HIGHLY toxic. When the shuttle lands you see it followed by large fans to blow away any residual hydrazine.
Anyone have anymore info regarding hydrazine use on the F-16?
Ptrjong From Netherlands, joined Mar 2005, 3768 posts, RR: 20 Reply 4, posted (6 years 7 months 1 week 5 days ago) and read 11369 times:
Found some info (in Dutch) on a Belgian website: http://users.telenet.be/lode.stevens/cma/Hydrazine.htm
The F-16 Emergency Power Unit (EPU) uses 'H70' which is 70% hydrazine and 30% water. A tank for approx 25 litres of H70 is situated on the RH side of the fuselage near the wing. When used, the EPU's exhaust gasses smell of ammonia and are believed to still contain hydrazine.
The article continues to sum up all the nasty hazards of hydrazine, I guess that's easy enough to find in your own language if you're interested.
After the recent Dutch F-16 crash at Volkel AFB firemen were seen in protective clothing as a precaution against a possible hydrazine leak.
It seems that the F-16 is about the only aircraft to use this stuff, together with the Space Shuttle - and the Messerschmitt Me 163 rocket fighter.
Peter
The only difference between me and a madman is that I am not mad (Salvador Dali)
Skyman From Germany, joined May 2006, 494 posts, RR: 0 Reply 5, posted (6 years 7 months 1 week 4 days 15 hours ago) and read 11317 times:
Ok thanks, so I gues that every F-16 crash has to have a hydrazinecrew there. I was just curious because some weeks ago there was a controlled crash of a USAF F-16 in the Pfalz about 300 meters away from a village and the people got really angry when they found out that they were so close to a crash zone. I don´t think they ever heard about hydrazine.
Quoting Ptrjong (Reply 4): Messerschmitt Me 163 rocket fighter.
Really the Komet used it too? Very interesting thanks.
HawaiianHobo From United States of America, joined Jan 2004, 149 posts, RR: 0 Reply 6, posted (6 years 7 months 1 week 4 days 12 hours ago) and read 11287 times:
In short, Yes.
H70 (hydrazine) is some of the most dangerous stuff I've ever worked with. In the US Air Force, Fuel Systems Mechanics are responsible for the H70 system upto the EPU itself. After that, it becomes E&E's job. EPU exhaust comes out of the F-16 at +1300?°F. Any time an F-16 comes in with an EPU activation, the only people allowed near the jet are the fire department and a hydrazine response crew (wearing Level B contamination suits with full air supplied respirator) from the fuel shop. The pilot isn't even allowed out of the cockpit until EPU contamination is contained or determined non-existant.
We were performing maintenance on a hydrazine bottle a few weeks ago, and despite all our precautions depressurizing the bottle and what not, about half a tablespoon of H70 leaked out of the nipple as we were changing it. That little bit of hydrazine spilled onto the bottle itself and was enough to send the bottle smoking for about 4 minutes. The toxic smoke could have sent me and my partner to the hospital faster than you could say "Fighting Falcon" but thankfully we were wearing chemsuits with respirators.
HawaiianHobo From United States of America, joined Jan 2004, 149 posts, RR: 0 Reply 8, posted (6 years 7 months 1 week 3 days 23 hours ago) and read 11216 times:
I can't speak for all aircraft, but in the USAF, only our single jet engine aircraft have an EPU system. The reason for this is because if the single engine fails, electrical and hydraulic failure is imminent. The EPU takes over and generates the required power for the electrical and hydro for about 10-15 minutes while the pilot glides his/her aircraft to a safe location and possibly bail out. With twin engine aircraft (or more) the chance of multiple engine failure is so small, that an EPU isn't necessary.
Now the EPU also comes on for other failures as well but I don't know them well enough.
L-188 From United States of America, joined Jul 1999, 29350 posts, RR: 62 Reply 9, posted (6 years 7 months 1 week 3 days 21 hours ago) and read 11206 times:
Jwenting From Netherlands, joined Apr 2001, 10213 posts, RR: 21 Reply 10, posted (6 years 7 months 1 week 3 days 12 hours ago) and read 11185 times:
Hydrazine was not used in WW2 AFAIK. Don't think it had been synthasised yet
T-Stoff was nasty enough as it is, and not the nastiest stuff thought up as fuel either.
Ptrjong From Netherlands, joined Mar 2005, 3768 posts, RR: 20 Reply 11, posted (6 years 7 months 1 week 3 days 5 hours ago) and read 11149 times:
With due respect, Jeroen, I'm quoting David Mondey's Consise Guide to Axis Aircraft of World War II on the Me 163:
The fuel was a mixture of 80 per cent hydrogen peroxide with oxyquinoline or phosphate (T-Stoff) and an aqueous solution of calcium permanganate (Z-Stoff). An imbalance of these fuels in the combustion chamber could cause an explosion and occasionally did; a replacement for Z-Stoff using a different catalyst (30 per cent hydrazine hydrate solution in methanol) was called C-Stoff and was developed for use in the (...) later Me 163B.
The only difference between me and a madman is that I am not mad (Salvador Dali)
L-188 From United States of America, joined Jul 1999, 29350 posts, RR: 62 Reply 12, posted (6 years 7 months 1 week 3 days 5 hours ago) and read 11145 times:
Correct me if I am wrong, but if you add water to Calcium Permangante, you get Actelyene?
Quoting Ptrjong (Reply 11): (30 per cent hydrazine hydrate solution in methanol) was called C-Stoff and was developed for use in the (...) later Me 163B.
Ok, but the question is did it make service by the wars end.
It is amazing how close the germans got to some concepts and chemicals right before the end.
OBAMA-WORST PRESIDENT EVER....Even SKOORB would be better.
CTR From United States of America, joined Jul 2005, 303 posts, RR: 0 Reply 15, posted (6 years 7 months 1 week 3 days ago) and read 11103 times:
Quoting Ptrjong (Reply 7): How do other fighters (other aircraft) manage? Another propellant?
Ram air turbine? No emergency power at all?
The F-16 is not only single engine it is also fly by wire and dynamically unstable. So when the cockpit goes black, even for a second, the aircraft can turn into a Frisbee. This is not the case with dynamically stable single engine hydro-mechanical control fighters like the A-4, F-5 and A-7s. Note these aircraft have accumulators to maintain hydraulic power for a (very) limited time.
Boeing4ever From , joined Dec 1969, posts, RR: Reply 16, posted (6 years 7 months 1 week 2 days 23 hours ago) and read 11091 times:
So question...
Will the F-35 feature a hydrazine EPU? It is after all a single engine fighter, though I'm not sure if it's dynamically stable. Alas, I'm an AE student, so it's not like I can eyeball a plane and tell if it's stable or not...yet.
I wondered the same myself, so I spoke to a friend at Lockheed Fort Worth. In the F-35, should the engine fail, the aircraft computers shed as much power as possible while the aircraft batteries maintain power to the flight controls until the IPP (Integrated Power Package similar to APU) gets up to full power.
HawaiianHobo From United States of America, joined Jan 2004, 149 posts, RR: 0 Reply 19, posted (6 years 7 months 1 week 15 hours ago) and read 10909 times:
Quoting CTR (Reply 18): In the F-35, should the engine fail, the aircraft computers shed as much power as possible while the aircraft batteries maintain power to the flight controls until the IPP (Integrated Power Package similar to APU) gets up to full power.
I wonder how the hydraulics will remain active on just battery power...? I know from working on current fighters that battery power alone doesn't do jack for the plane aside from running a few gauges and a DC fuel pump or two. And if you run battery power alone on a C-130 for more than 10 minutes alone, you kill the damn thing, and its got 2 batteries!
This IPP you speak of sounds intriguing. I suppose the hydraulic system could be tied into DC but I just can't imagine it punching out 3000PSI for very long. At least not the 15 minutes the hydrazine and EPU system keeps the F-16 and U-2 up there.
CTR From United States of America, joined Jul 2005, 303 posts, RR: 0 Reply 20, posted (6 years 7 months 1 week 14 hours ago) and read 10905 times:
Quoting HawaiianHobo (Reply 19): I wonder how the hydraulics will remain active on just battery power...?
The primary flight controls on the F-35 are EHAs (Electro-Hydraulic Actuators) that are powered by 270 VDC in place of traditional hydraulic power. So hydraulics are not critical imediately following engine failure, but electrical power demand is very high.
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