Aces High Bulletin Board
General Forums => The O' Club => Topic started by: Wayout on May 23, 2011, 07:30:18 AM
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Lockheed SR-71 Blackbird. A little different look. :salute
http://wimp.com/lockheedblackbird/ (http://wimp.com/lockheedblackbird/)
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neat vid :aok
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Its such a beautiful plane, but such a waste of fuel at launch :uhoh
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Now if we could get the squirrels with cameras into those bad boys, we'd always be safe!
Its such a beautiful plane, but such a waste of fuel at launch :uhoh
Yeah, can you say fire hazard? That stuff was leaking all over the place.
-Penguin
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Now if we could get the squirrels with cameras into those bad boys, we'd always be safe!
Yeah, can you say fire hazard? That stuff was leaking all over the place.
-Penguin
I recall hearing JP-7 is a type of diesel fuel, and that doesn't light easily. Or I may be completely wrong, please correct me or point me in the right direction.
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There's a JP-7? I learn something new every day.
-Penguin
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There's a JP-7? I learn something new every day.
-Penguin
Did you watch the video? They talked about using JP-7.
JP-7 was a specialty fuel designed for the SR-71 for it's low flashpoint.
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I must have had to alt-tab right then, I'm typing this during our joke of a computer programming class.
-Penguin
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Did you watch the video? They talked about using JP-7.
JP-7 was a specialty fuel designed for the SR-71 for it's low flashpoint.
So was I sort of right? I confused it with JP-5 on accident but same principle with the lower chance of igniting.
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So was I sort of right? I confused it with JP-5 on accident but same principle with the lower chance of igniting.
I'm no expert on the stuff, but IIRC, it has similar properties to diesel fuel.
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I've waded around in a lot of diesel fires and jet fuel fires....you can't tell them apart at that point.
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buying titanium from the Russians for it? thought we were butting heads during her service.... jump start from 2 454 engines on just 1 engine? jeebus.... and refueling after only a few minutes in flight? nuts. how id love a ride in such a beautiful, historic bird.
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Great video, that website is very interesting.
I also heard, on the History Channel, that the SR can reach staggering tempratures from the air rushing past its surface at such high speeds. Is this true?
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Great video, that website is very interesting.
I also heard, on the History Channel, that the SR can reach staggering tempratures from the air rushing past its surface at such high speeds. Is this true?
Its the friction of the air moving so fast over the frame. So yes it is true.
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I recall hearing JP-7 is a type of diesel fuel, and that doesn't light easily. Or I may be completely wrong, please correct me or point me in the right direction.
Yeah they made a special tanker just for the blackbird to carry it. I believe you couldn't light it on fire with a blowtorch.
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I've been in avaition for over 40 years now and I've seen a lot of things, some good, some bad and some tragic; it takes a bit to impress me. The SR-71 still does.
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refueling after only a few minutes in flight? nuts.
If you factor in the fuel leaks, the high power requirement for takeoff, and it being horribly inefficient during low speed and low altitude flights then this explains why it empties its tanks after takeoff. Once up to speed (and altitude) it could fly for an extremely long distance without requiring another refueling as the fuel leaks would seal up and things become much more efficient at that point.
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If you factor in the fuel leaks, the high power requirement for takeoff, and it being horribly inefficient during low speed and low altitude flights then this explains why it empties its tanks after takeoff. Once up to speed (and altitude) it could fly for an extremely long distance without requiring another refueling as the fuel leaks would seal up and things become much more efficient at that point.
The faster it went less gas was burned. Interesting fact.
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The faster it went less gas was burned. Interesting fact.
Once you punch the sound barrier you glide more smoothly through the air and efficiency goes up.
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JP-7 has a very HIGH flashpoint of about 60 °C (140 °F) and needs to be compressed to be ignited.
Compressing the fuel builds heat to produce vapor. Standing JP-7 will not ignite.
Gasoline on the other hand has a very LOW flashpoint, -43 °C (-45 °F) and will iginte in the presence of ignition source.
The flashpoint of a fuel is the temperature at which vapor is emmited, and can be burned. No vapor, no fire.
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JP-7 has a very HIGH flashpoint of about 60 °C (140 °F) and needs to be compressed to be ignited.
Compressing the fuel builds heat to produce vapor. Standing JP-7 will not ignite.
Gasoline on the other hand has a very LOW flashpoint, -43 °C (-45 °F) and will iginte in the presence of ignition source.
The flashpoint of a fuel is the temperature at which vapor is emmited, and can be burned. No vapor, no fire.
Yes, I got that mixed up, thanks for clarifying.
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Still remember the baseball All-star game at Oakland Coliseum that had a SR-71 overflight. Loud as heck and I almost spilled the beers I was bringing back to the seats.
I know spilling beers is almost a crime but in this case it would have been justified.
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I've been in avaition for over 40 years now and I've seen a lot of things, some good, some bad and some tragic; it takes a bit to impress me. The SR-71 still does.
RGR that.
RTR
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JP7 lights just about as easy as water... Not very :rofl
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I've been in avaition for over 40 years now and I've seen a lot of things, some good, some bad and some tragic; it takes a bit to impress me. The SR-71 still does.
The "Blackbird" is one of the planes built before its time. It could still be operated as a top tier "Spy" bird creating intelligence on a moments notice. It is still faster to launch a spy plane that is in the system than it is to re-task a satellite. Satellites can be defeated if the other side has counter intelligence assets in place to locate tasked satellites. It is hard to tell if a SR-71 is coming your way. I have heard first hand stories from pilots involved with the projects how awesome and handy these planes were to the intelligence community. The Drone community has taken some of the missions that the SR-71 maintained but the Drones are still not in the same league as the "Blackbird". Salute the plane and the crews that were involved with the project.
JUGMAN
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Anyone ever seen an RC Blackbird?
http://www.youtube.com/watch?v=SDbQ5xvsrIU
OMFG!
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cool video. I bet that toy would have made Kelly Johnson proud .
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At mach3 at 70K plus the pilots were always flying on the edge of stalling due to the scarcity of air at that altitude. A stall at that speed almost always meant destruction of the plane and death to the crew. The plane took constant attention. The crew were brave and skilled. :salute
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Anyone ever seen an RC Blackbird?
http://www.youtube.com/watch?v=SDbQ5xvsrIU
OMFG!
Holy crap! :O :O Thats freaking huge!
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Holy crap! :O :O Thats freaking huge!
Direct your attention to these
C-17
http://youtu.be/c5FjTcctkC4 (http://youtu.be/c5FjTcctkC4)
B-29 with X1
http://youtu.be/5x291HbsyDI (http://youtu.be/5x291HbsyDI)
Even bigger B-29
http://youtu.be/KmKdA6L_MWk (http://youtu.be/KmKdA6L_MWk)
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Direct your attention to these
C-17
http://youtu.be/c5FjTcctkC4 (http://youtu.be/c5FjTcctkC4)
B-29 with X1
http://youtu.be/5x291HbsyDI (http://youtu.be/5x291HbsyDI)
Even bigger B-29
http://youtu.be/KmKdA6L_MWk (http://youtu.be/KmKdA6L_MWk)
I've seen all of them before, the SR-71 took me by surprise. The B-29 with the X1 is amazing though! It takes 3 people to fly, 2 to fly the B-29 and 1 for the X1
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The fuel is so hard to ignite that tri-ethyl borane is injected into the combustion section
to light it. Tri-ethyl borane is a highly toxic liquid that spontaneously ignites with air and
carries a distinctive green flame.
Link to the SR-71 flight manual...
www.sr-71.org/blackbird/manual/ (http://www.sr-71.org/blackbird/manual/)
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The fuel is so hard to ignite that tri-ethyl borane is injected into the combustion section
to light it. Tri-ethyl borane is a highly toxic liquid that spontaneously ignites with air and
carries a distinctive green flame.
Link to the SR-71 flight manual...
www.sr-71.org/blackbird/manual/ (http://www.sr-71.org/blackbird/manual/)
So does a large supply of it have to be taken?
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No, once the fuel is ignited the combustion is self sustaining.
The most important characteristic of JP-7 is the low vapor pressure, it was designed
that way to prevent boil off at high altitude. A secondary design characteristic is the
very high ignition temperature so the fuel can be used as a coolant.
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No, once the fuel is ignited the combustion is self sustaining.
The most important characteristic of JP-7 is the low vapor pressure, it was designed
that way to prevent boil off at high altitude. A secondary design characteristic is the
very high ignition temperature.
I was just thinking about that, after the engines start the combustion chamber will be extremely hot, so I figured the fuel would just ignite from the super high temperatures. It all makes sense now, there's so much to know about all this. I'm very eager to learn.
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The SR-71 suffers from a condition known as an unstart, the engine ingests supersonic
air and the compressor stall. The abrupt asymmetrical thrust has been known to yaw
the aircraft so hard that helmets were cracked. The onboard computer automatically
adjusts the inlet spike to reestablish subsonic airflow and combustion is restored, usually.
At times this process has occured without the crew even noticing the problem, only once
the maintence crew checked the logs did they become aware.
Rather interesting phenomenon, its covered pretty well in the flight manual...
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The SR-71 suffers from a condition known as an unstart, the engine ingests supersonic
air and the compressor stall. The abrupt asymmetrical thrust has been known to yaw
the aircraft so hard that helmets were cracked. The onboard computer automatically
adjusts the inlet spike to reestablish subsonic airflow and combustion is restored, usually.
At times this process has occured without the crew even noticing the problem, only once
the maintence crew checked the logs did they become aware.
Rather interesting phenomenon, its covered pretty well in the flight manual...
I recall hearing about this on Great Planes. The ducts moved forward and aft to adjust the air flow to prevent supersonic air from entering and stalling the compressors. Its what I recall off the bat. I also saw this technology on Wings of the Luftwaffe about the ME-262, used in the exhaust, the bullets could be retracted or extended to allow for more thrust speeds or something along the lines of that. This must have been reverse engineered to go over the intake aside from the exhaust duct. Am I right at all or am I speaking Gibberish?
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Although the Me-262 did have a rear bullet it bears little in relationship to the inlet spike
of the SR-71. The bullet was designed to produce a variable exit area which maintained
the proper exit velocity.
Here is some good engineering material on the Junker Jumo 004 used by the Me-262....
http://www.enginehistory.org/German/Me-262/Me262_Engine_2.pdf (http://www.enginehistory.org/German/Me-262/Me262_Engine_2.pdf)
The SR-71 inlet spike is designed to steer a shockwave into a specially shaped area of
the inlet section. The shockwave is reflected and slowed so that the air becomes subsonic
and able to be compressed. An unstart occurred when the center body shock wave was
ingested into the throat inlet.
(http://www.456fis.org/THE%20J-58%20ENGINE/InletDesign.gif)
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Although the Me-262 did have a rear bullet it bears little in relationship to the inlet spike
of the SR-71. The bullet was designed to produce a variable exit area which maintained
the proper exit velocity.
Here is some good engineering material on the Junker Jumo 004 used by the Me-262....
http://www.enginehistory.org/German/Me-262/Me262_Engine_2.pdf (http://www.enginehistory.org/German/Me-262/Me262_Engine_2.pdf)
The SR-71 inlet spike is designed to steer a shockwave into a specially shaped area of
the inlet section. The shockwave is reflected and slowed so that the air becomes subsonic
and able to be compressed. An unstart occurred when the center body shock wave was
ingested into the throat inlet.
(http://www.456fis.org/THE%20J-58%20ENGINE/InletDesign.gif)
If steers the shockwave, I mean thats alot of energy I would assume right? I mean do the intake spikes get battered often? I mean I understand how it works in general to reflect the waves/shocks but to me it would seem the spike takes a good beating? Sorry If I might not catch on, I'm eager to learn but its hard to take in alot.
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Depends on how you look at it, the air is so thin that the main concern is aerodynamic
heating, the brunt of a the shockwave is only felt at the very tip of the spike. You will
notice a shine silver tip on the inlet spike, I believe that is Rene 41 but I could mistaken.
Regardless of the name it was a very high temp durable metal, the remainder of the spike
was titanium.
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I'm no expert on the stuff, but IIRC, it has similar properties to diesel fuel.
Most jet fuel does, as well as Keorsene. I used to fuel aircraft at the local international airport and we ran jet-a in our diesel trucks. Occasionally a mechanic would trundle over and dump some ATF into the tank for lubrication.