REAL PERFORMANCE of RD-33 and much more...

[RvETito]

That's correct Pilotasso, however I was reffering to engines only.

[4c Hajduk Veljko]

And the SR-71 top performance is still classified, so comparing the MiG-25 to the SR-71 is like comparing apples to some experimental gene enhanced orange.

No, it is actually comparing apples to apples. Because SR-71 held the altitude record in that same class. Until RD-33 engines came into play … :smilewink:

[4c Hajduk Veljko]

By-pass engines are not that good in high altitude compared to turbojets. Their power is limited due to fan overspeed, so I wouldn't pay attiention to that 'record' of the MiG-29- being much lighter and with much bigger t/w ratio that the MiG-25 how come it can reach balistic ceiling 10km less. Hell even the MiG-23MLD has much better performance above 18000m than the 29.

Thanks, for clearing that up. I don’t know anything about jet engines. The MiG-29 altitude record I found in the “

“MiG 29 Flight Manual: Declassified”, by Alan R. Wise, Page 6. It is very interesting reference book and somewhat difficult to read.

[RvETito]

Hajduk Veljko, I think you are overestimating the RD-33. MiG-29's flight manual says service ceiling 18000m, are you saying that this number should be now changed to 27000+ m? MiG-29 can't maintain level flight at that altitude- these records are always set in balistic climb. The SR-71 (and it's engine) is totaly different case, it cruises at such altitude. Same class (12000-15000 kg)- now way! The Blackbird is much heavier, not to mention that it's records are 'unofficial', I mean how do you imagine someone of FAI would be allowed to track it?

 

From the theory- at speed above Mach 1.5-1.6 the turbofan engine steps behind the turbojet in terms of efficiency. The main advantages of the bypass engine are in the subsonic and transonic range, where most of the modern fighters powered by turbofans operate.

 

Don't make the 29 and it's engine something they aren't.

[Groove]

I like Hajduk`s Mig-29 to SR-71 comparision. Such postings makes him sympathic.

[4c Hajduk Veljko]

MiG-29's flight manual says service ceiling 18000m, are you saying that this number should be now changed to 27000+ m?

No, I do not say that. I was talking about altitude record set by MiG-29. And it just happens that MiG-29 uses RD-33 engines. That’s it.

 

Same class (12000-15000 kg)- now way!

It is not the same class airplane from the military point of view. It is the same class airplane form the FAI (Federation Aeronautique Internationale) competition point of view. And it just happened that SR-71 and MiG-29 are in that same class from the FAI competition point if view. That’s the reason why I provided a link in my previous post, so that one can go to FAI web site and see what is all this about. Somebody correct me if I am wrong about this classification.

 

Don't make the 29 and it's engine something they aren't.

I am not. However, it is impressive to see altitude (or any other type of) record set by an airplane that uses engines that are the subject of this thread.

[Yo-Yo]

Yes, but benchtest figures aren't normally published for the lower density atmosphere that occurs at altitude.

 

 

The benchtest figures represent numbers of test points either at different altitudes or speeds. Of course the speed is equivalent speed because the chamber inflow has its own speed higher than it would be in open air..

The main differences between benchtest and the real engine is that the inlets for the test has very high pressure recovery coeff value (~1) and the real inlets can have lower values because of their construction.

[D-Scythe]

No, I do not say that. I was talking about altitude record set by MiG-29. And it just happens that MiG-29 uses RD-33 engines. That’s it.

 

It is not the same class airplane from the military point of view. It is the same class airplane form the FAI (Federation Aeronautique Internationale) competition point of view. And it just happened that SR-71 and MiG-29 are in that same class from the FAI competition point if view. That’s the reason why I provided a link in my previous post, so that one can go to FAI web site and see what is all this about. Somebody correct me if I am wrong about this classification.

 

I am not. However, it is impressive to see altitude (or any other type of) record set by an airplane that uses engines that are the subject of this thread.

 

What altitude record? You do know that the SR-71 can also ballistically propel itself higher than its ~70 000ft cruise altitude right? In fact, IIRC, the SR-71 can reach altitudes well in excess of 100 000ft flying that type of profile.

 

Really, what the MiG-29/RD-33 did was NOTHING special - the F-4 Phantom likewise also had an absolute altitude record of ~98,500ft (30 000m). The MiG-29 is no better than an F-4 in this case. In fact, it's several thousand feet worse.

 

But I'm not you. Nobody's going to hear me jump to the conclusion that "Those J79s are some engines!"

[tflash]

Well D-Scythe, GGTharos, if you guys find an altitude of 27,460 meters (90,092 feet) "nothing special", you have another opinion on aerodynamics, the stratosphere and aviation in general than I do.

 

But, then, who am I? Certainly NOT a person that has flown an aircraft at that altitude, I confess.

[tflash]

And you find the U2 "nothing special" and Gary Powers maybe a "mediocre pilot" ?

 

I think some of us identify themselves so much with top performances that they seEm to think there is nothing to it.

 

I say: taking a Mig-29 to that altitude is NOT an everyday feat. There is nothing wrong with Hajduk's statement, there is something VERY boring about his detractors.

[Avimimus]

The Mig-29 is still performing impressively. What could an F-16 do? Made with less sophisticated equipment...

[britgliderpilot]

I find nothing special about the U2 flying high. Currently at the moment the highest flying aspirated engine aircraft is a propeller driven wing developed by NASA. Ill look for the information in a bit, unless you know which aircraft I am referring to. As far as Gary Powers being a mediocre pilot, theres nothing special about flying an aircraft that WANTS to fly at that altitude. Mind you there are astronauts that are in space for months on end at triple that altitude.

 

Edit: http://www.aviationtrivia.homestead.com/Helios.html

 

Helios is solar-powered - no burning of fuel involved there . . . .

 

 

From everything I've read, Gary Powers was anything but a mediocre pilot.

In fact he was the most experienced U-2 pilot there was, chosen for a marathon mission . . . . only reason he got shot down is that his overflight followed a previous entry route to Soviet airspace and fourteen SAMs were waiting for him.

I consider his survival astonishing.

 

And the U-2 should be considered an extremely challenging aircraft to fly at the extremes of it's performance . . . .

[Pilotasso]

And you find the U2 "nothing special" and Gary Powers maybe a "mediocre pilot" ?

 

I think some of us identify themselves so much with top performances that they seEm to think there is nothing to it.

 

I say: taking a Mig-29 to that altitude is NOT an everyday feat. There is nothing wrong with Hajduk's statement, there is something VERY boring about his detractors.

 

 

Who are the "detractors"? :huh:

[S77th-GOYA]

Comparisons between the MiG and F-16 can only go so far. The F-16 only has one engine.

[Pilotasso]

Doesnt mean much since their T/W isnt very different at sea level. Now the question of the shockwave optimization in a variable air inlet is another ball game. Does the Mig have such?

[D-Scythe]

Well D-Scythe, GGTharos, if you guys find an altitude of 27,460 meters (90,092 feet) "nothing special", you have another opinion on aerodynamics, the stratosphere and aviation in general than I do.

 

But, then, who am I? Certainly NOT a person that has flown an aircraft at that altitude, I confess.

 

Tflash, you have got to be kidding me. An altitude of 27460 meters is great, but only if you can actually fly that high. The MiG-29 cannot - it reached that altitude on a ballistic zoom climb. That means that the pilot basically went really fast than pulled the jet straight up and kept it there until the plane simply ran out of speed and dropped back down to a controllable altitude - like a manned rocket.

 

Just because a plane can reach 90 000ft in a ballistic zoom climb doesn't mean it can fly at 90 000ft. The basic idea of a zoom climb is to go as fast and as high as possible at altitudes your plane *can* fly in so that you can pitch up and go as high as you can at altitudes you *cannot* fly in.

 

Ninety thousand feet is nothing special. Again, the F-4 ranked in 8 000ft higher.

 

And you find the U2 "nothing special" and Gary Powers maybe a "mediocre pilot" ?

 

I think some of us identify themselves so much with top performances that they seEm to think there is nothing to it.

 

I say: taking a Mig-29 to that altitude is NOT an everyday feat. There is nothing wrong with Hajduk's statement, there is something VERY boring about his detractors.

 

Wow, reading into things much? Sure, taking a MiG to angels 90 may be an impressive feat for the PILOT, but Hadjuk was trying to attribute that impressiveness to the airframe and the RD33 engines. Nobody said anything bad about the pilot, so I have NO idea what you're trying to start here.

 

Seriously, WHERE are you going with this?

[RvETito]

Doesnt mean much since their T/W isnt very different at sea level. Now the question of the shockwave optimization in a variable air inlet is another ball game. Does the Mig have such?

 

Yes, it's indication is even modelled in LO- the instrument "КЛИН" under the fuel gauge.

[Vekkinho]

Yes, it's indication is even modelled in LO- the instrument "КЛИН" under the fuel gauge.

 

...but is it working?!

[RvETito]

The gauge- yes, the two arrow indexes move with Mach number increase/decrease, both in the MiG and the Su. About how this is taken into account in the physical model- I can't tell but if it's not modelled it shouldn't be possible to reach Mach 2.4.