Holy Moly! sr-71 top speed is Mach 14 (leaked document)

Originally posted by C0bzz
What if an Airforce pilot has a degree in Aerospace Engineering?

Like I said, you fly boys crack me up.

I *think* test pilots are required to...

reply to post by kilcoo316


NASA looked at modifying it to do Mach 3.5 because it couldn't do it all the time, and it couldn't SUSTAIN Mach 3.5. The flight that Brian Shull hit Mach 3.5 he said that it was the fastest he had EVER gone in an SR-71 and he never went that fast again, and he flew the SR for many years. It was a ONE TIME event. NASA wanted to modify them to do it EVERY FLIGHT and to be able to SUSTAIN that speed.

reply to post by Travellar


Actually it is a trainer SR-71B #61-7956 shown on the ramp. See this link:

www.sr-71.org...

Originally posted by Zaphod58
NASA wanted to modify them to do it EVERY FLIGHT and to be able to SUSTAIN that speed.

You might be right there, i.e. if your willing to risk damage you can push to over Mach 3.4something.


I'll dig some more and post back.

reply to post by kilcoo316


Willing to risk/ and or accidently push it over the mach 3.4 "limit"

Ok, here we go:

Lockheed secret projects - Inside the skunk works
Zenith Press

Dennis R. Jenkins

The maximum performance of the Blackbird is only now becoming well understood. The SR-71 was intended for flight at altitudes approaching 85,000 feet, with sustained cruise speeds approaching Mach 3.2. The smaller and lighter A-12 could better each of these by a small margin. During its operational career, the SR-71 rarely exceeded these design speed or altitude limits. Studies have been conducted by Lockheed and NASA that show speeds in excess of Mach 3.5 could be achieved for 10 to 15 minutes. The studies indicated that increasing the maximum speed to Mach 3.4 would not require any additional modifications to the aircraft, but for sustained flight between Mach 3.4 and Mach 3.5, the inlet hydraulic lines and actuators would need to be better insulated to protect them from the additional heat. NASA had planned to conduct an envelope expansion program for the SR-71, but ever tightening budgets led to these plans being canceled in the early 1990s. The only structural limitation related to speed above Mach 3.5 is an absolute limit of 420 knots equivalent airspeed (KEAS), set by inlet duct temperatures and pressures which exceed acceptable values. Other factors that limit speed above Mach 3.5 are inlet capture area and excessive engine compressor inlet temperatures (CIT).

One of the NASA studies also addressed achieving higher altitude flight. The results indicated that a "zoom climb" profile would allow reaching 95,000 feet for a short time with an aircraft gross weight of approximately 85,000 pounds. The aircraft would be accelerated from Mach 3.2 to Mach 3.5 at an altitude of 80,000 feet, then zoomed to 95,000 feet, with speed decaying back to approximately Mach 3.2. The aircraft would subsequently settle back to an altitude of 84,000 feet. Factors which limit sustained flight at altitudes above 85,000 feet are wing area and total thrust. It would be possible to replace the outer wing panels with larger ones to provide additional wing surface area and allow sustained flight above 85,000 feet.

Here is the SR-71 Flight Manual..

www.sr-71.org...


www.sr-71.org...

Originally posted by GrndLkNatv
Here is the SR-71 Flight Manual..

www.sr-71.org...


www.sr-71.org...

Thank you for the links.


They state a design Mach of 3.2, and upper limit of Mach 3.3 at the flight commander's discretion.


Clear as mud eh?

Yeah but you know some people will still insist the flight manual is just government disinfo and that it can really do Mach 15 and fly in low earth orbit

Well, there is more to determining top speed than one simple equation.

One should study aerodynamics further.

As far as ultimate top speed of the SR-71 and its versions;

Mach 14 is a bit out of touch for the sr-71.

However 3.5 is far from its actuall top speed.

Mach 7.2 to an upper limit of mach 10 would be a better guess.

My uncle was stationed on a base where the Sr-71 's were flying out of. He claims to have clocked them at Mach 7. He said you would watch them take off, then you would see the afterburners light up, here a loud noise, and the thing was f'in gone.

reply to post by Darthorious

First off, wrong. The SR-71 had three different fuel configurations for take off. No, it didn't use all of its fuel just to get off the ground. Please get your facts straight.

reply to post by BigTrain


You have to keep in mind that you're talking about technology 30 years old. Do you believe the stealth bomber was concieved and created in a weekend? OF course not. Its been in development 30 years prior to it's arrival on scene.
What technology we see 30 years from today, will not be created 30 years from now. It is being created and developed today.

reply to post by warthog911


I´m aware that we talk about serios topics here, but this kind of source( if such name can be applied) its a joke. Many green aliens, many MIB. The design top speed of SR-71 is close to mach 4, but the engines are not design to sustain that speed for a long time. It is known that Blackbird has reach such speeds unofficially, evading SAM´s over North Vietnam sky.

reply to post by warthog911


Hate to burst your bubble but the SR-71 Blackbird only got to Mach 3.5. Inlet compression temperature keeps the SR-71 Blackbird from going faster. That article is nothing more than BS.

Ok my turn to weigh in on this sillyness. Lol. I'm pretty sure the only man made objects achieving mach 14 are space vehicles and now some solid projectiles being fired from railguns. My dad was in the air force and flew f-111's and he had a friend, Blair Bozek, who flew sr-71s and had to eject from one incidentally, google all of this for proof, and he claims the aircraft could fly much faster and higher than the published numbers. I took that to mean probably close to or slightly above Mach 4 and higher than 100,000 ft. As far as I can tell, it seems the only high speed limitations would be temperature limitations. It seems to me that the aircraft had enough thrust to propel it to thermal destruction at altitude. As far as the max altitude goes, meh, I don't care too much for that. I think the speed is more interesting. I listened to Richard Graham speak about flying the sr-71 at eaa oshkosh airventure and he said the highest external temperature reached during his flights was around 622 fahrenheit right at the base front of the cockpit glass, and that is where he heated up his tube food by placing it on the dash for 1.5 minutes a side lol. I think mach 4 was feasible, but I imagine there were temperature constraints. It's extraordinarily hard to push things through the air that fast. That is why the top speed for a production car is only 258 with the shelby supercar and that thing is using 1150 horsepower, absolutely ridiculous! As far as the antigravity technology for the B-2, whoever believes in that is drinking drano. lol. Why would they put wings on it if they had anti-gravity duhhhhhh. If you are still a skeptical moron, watch the b-2 crash on youtube, or just start taking engineering classes and learn more. Absolutely ridiculous. I mean cmon people, apply some logic! Read some more! Jeez. Oh by the way, an australian training with my dad's squadron got the F-111 up to 1263 knots indicated air speed 200 ft above the deck in death valley california in the 1970's. Fastest low level airspeed of any aircraft ever. Unless somebody comes up with a number for the Mig-25, which seems like the only other aircraft I could think of approaching that speed. 1263, thats what the analog said. The guy's name was Andy Pellequin. He was notorious for doing alot of other things that were looked down upon as well.

Originally posted by Anonymous ATS
reply to post by BigTrain

 

You have to keep in mind that you're talking about technology 30 years old. Do you believe the stealth bomber was concieved and created in a weekend? OF course not. Its been in development 30 years prior to it's arrival on scene.
What technology we see 30 years from today, will not be created 30 years from now. It is being created and developed today.

There is usually a difference between development of systems/solutions (combat aircraft are considered a solution) and development of new technology.

There are meta-materials out there that allow for manipulating electromagnetic energy in all kinds of different ways. They were developed in the 'open' world by universities and industries. Those are, generally, new technology.

What is/was developed in places like Groom Lake is a solution. Often, all they do is take pre-market technologies (paints that don't have FDA approval, because we're trained not to eat paint) and other technology that has not yet been implemented in a cost-effective (or even a cost-ineffective) manner in the civilian world.

It should be noted that the goals of developing a research/demonstrator/prototype aircraft are considerably different from an aircraft expected to be in main-line inventory. Developing an aircraft you only expect to produce one or two of is going to be expensive no matter how you slice it - may as well take the time to use all of the fancy new developments in the world that no one else has really figured out what to do with, yet. But, for something you plan to build a thousand or more of, you are going to stick to more proven ground - especially when you consider mass-production for many of the involved components is available. This is why some of the 'state of the art' systems the military uses have more in common with an Atari than a modern computer - most of the stuff the military uses was built twenty years ago, and the military hasn't invested in keeping up with the fast-paced electronics market.

Just because it's "classified" doesn't make it frontier or of alien origin. Almost everything that is classified is not given its classification level because it is 'advanced' - it is just not something that needs to be common knowledge - such as sonobuoy drop patterns, communications frequencies, specific alloys used in chaff, etc. We don't necessarily use advanced systems to make the stuff - it's just that time and money has been spent developing it and figuring out what works 'best' - giving that away to potentially be used against us is just not smart.

I saw a documentary of the SR-71 and during the years of operation an SR-71 was flying over Russia and was shot upon by an Ground to Air Missile. If you do some research on what missiles were operational at the time and what speeds they could do you would see them ranging from mach 4-6. Supposedly they laid into it and let all 68,000lb ft of thrust eat to temperature close to the point at which titanium melts which is 1670C or 3040F. The plane is not limited by the engines capabilities but rather by the temperatures at which the titanium melts. Theoretically speaking it could reach speeds of around 4,500mph which is mach 5.91 before the plane completely melts.

During this SR-71 flight they laid into it and let the 68,000 lb ft of thrust at a classified altitude and verified that they reached speeds beyond mach 4 and they confirmed that they were seeing mach numbers that they had never seen before! The pilots said they were getting nervous as the plane cut through the sky like a molten hot knife through butter! hahaha So who knows what speeds they reached exactly but from a Mathematical stand point the plane could potentially reach speeds of up to mach 5.91 or around 4,500rpm. Depending on parameters of air thickness, temperature of the air, the air pressure, altitude, weight of the aircraft at altitude, engine output at altitude, etc, etc will give you the speed at which the titanium melts. Because after all 68,000 lb ft of thrust was a lot back then!

Now think about the YF-22 and YF-23 both having two new radical thrust vectoring engines putting out 30,000 lb ft of thrust per engine. The YF-22 can reach speeds of mach 2.2 because of the fixed geometry air intakes. The YF-23 can reach speeds of 2.2+ or 1,650mph+ because of it's variable geometry air intakes. The geometry of the air intakes has an effect on radar signature. The YF-23 had a further combat radius than the YF-22, had a further range than the YF-22 and could go faster than the YF-22. So I don't exactly get why they chose the YF-22 when the YF-23 on paper is clearly a better aircraft. When a YF-22 gets beat by a damn F-15 Eagle traveling at 1,700mph and the little YF-22 only pulling off 1,500mph. Even know the YF-22 has huge power output the fixed geometry intakes are limiting it's top end speed. Quite sad. However the YF-22 will out accelerate any jet plane damn up to 1,450mph or so because of the fixed geometry intakes it has better back pressure for increased burst acceleration. I think the YF-23 should accelerate just as fast but even know it has variable geometry intakes it weighs more than the YF-22 so it won't accelerate as fast.

reply to post by warthog911


So? The flux liner could go something like mach 25? Have a look at official anti-grav research in the tech journals before 1954, it all went black afterwards. T.Towns & Brown any bell?

Originally posted by chris89
Now think about the YF-22 and YF-23 both having two new radical thrust vectoring engines putting out 30,000 lb ft of thrust per engine. The YF-22 can reach speeds of mach 2.2 because of the fixed geometry air intakes. The YF-23 can reach speeds of 2.2+ or 1,650mph+ because of it's variable geometry air intakes. The geometry of the air intakes has an effect on radar signature. The YF-23 had a further combat radius than the YF-22, had a further range than the YF-22 and could go faster than the YF-22. So I don't exactly get why they chose the YF-22 when the YF-23 on paper is clearly a better aircraft. When a YF-22 gets beat by a damn F-15 Eagle traveling at 1,700mph and the little YF-22 only pulling off 1,500mph. Even know the YF-22 has huge power output the fixed geometry intakes are limiting it's top end speed. Quite sad. However the YF-22 will out accelerate any jet plane damn up to 1,450mph or so because of the fixed geometry intakes it has better back pressure for increased burst acceleration. I think the YF-23 should accelerate just as fast but even know it has variable geometry intakes it weighs more than the YF-22 so it won't accelerate as fast.

edit on 19-12-2012 by chris89 because: (no reason given)

edit on 19-12-2012 by chris89 because: (no reason given)

Something i posted a while back on the yf23...

my question to all would be, does anybody know why the F-22 was picked over the YF-23 when the latter had far better performance and such? I'm willing to bet that the F-22 went into production in the white world while the FB-23 or some R variant stayed black world. Sure would explain alot of sighting of triangle shaped aircraft with it's delta wing design. Just food for thought.

Now we have reports that two black world protects are running side by side out at groom. I'm gonna throw out an educated guess that we are looking at the rf23 and the new bomber. Just another thought.