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Andrey Tupolev's Tu-144 patent

flateric

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Not unbuilt, but deserves a mention
http://www.google.com/patents?id=7398AAAAEBAJ&printsec=abstract&zoom=4#PPA63,M1
 
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Lee

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There's also these:

http://www.google.com/patents?id=52EuAAAAEBAJ&dq=supersonic+ininventor:tupolev&as_drrb_ap=q&as_minm_ap=1&as_miny_ap=2008&as_maxm_ap=1&as_maxy_ap=2008&as_drrb_is=q&as_minm_is=1&as_miny_is=2008&as_maxm_is=1&as_maxy_is=2008&num=100

http://www.google.com/patents?id=KKs5AAAAEBAJ&dq=supersonic+ininventor:tupolev&as_drrb_ap=q&as_minm_ap=1&as_miny_ap=2008&as_maxm_ap=1&as_maxy_ap=2008&as_drrb_is=q&as_minm_is=1&as_miny_is=2008&as_maxm_is=1&as_maxy_is=2008&num=100


The TU-144 wasn't terribly efficient as an SST and toward the end of its commercial schedule, the manufacturer had to resort to installing bigger engines with better compressors to avoid using the afterburner after the plane was modified to add about 3m to the length 1.5m to the wingspan in the 'B' model.

Then it would have been fairly competitive with the Concorde.
 

KJ_Lesnick

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Lee said:
The TU-144 wasn't terribly efficient as an SST and toward the end of its commercial schedule, the manufacturer had to resort to installing bigger engines with better compressors to avoid using the afterburner after the plane was modified to add about 3m to the length 1.5m to the wingspan in the 'B' model.

From what I remember the Tu-144 prototype and Tu-144 production models both required afterburner for Mach-2 flight and as a result had a short range. At least the Tu-144 production model could do Mach 1.6 without afterburners.

The prototype Tu-144 was shorter, featured a simple double-delta wing, a 5-abreast fuselage (thicker than the Concorde) and two paired engines so close to each other that it looks like it's a single four engine box from some angles.

The production Tu-144 was longer, featured a more complicated delta-wing design and a retractable canard with slat and flap to allow the elevons to droop as flaps. Engines were spaced further apart but in rectangular-structures like before with two engines each.

It's the Tu-144D that could do Mach 2 performance without afterburner -- To my knowledge the basic airframe was either the same or largely the same as the standard Tu-144. The difference was the engines. Although I'm not sure about the specifics of that. I've been told
-The engine was a turbojet, unlike the turbofans used on the previous designs.
-The plane used the NK-321 Turbofan
-The plane used a variable-cycle engine which was believed to be beyond the Russians capability in 1970 when they began development by US estimates.

I'm not sure which.
 
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Lee

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KJ_Lesnick, quoted: "From what I remember the Tu-144 prototype and Tu-144 production models both required afterburner for Mach-2 flight and as a result had a short range.

Right. To get the advertised range, something like 90% of the payload weight had to be taken off. It might do about 3000 mile then and at high altitude. Also, there was a description---I think in Aviation Week---that passengers had to yell at each other ;D :mad: ::) over the engine's exhaust thunder.




KJ: "At least the Tu-144 production model could do Mach 1.6 without afterburners."

I didn't know it was that fast on just dry thrust. Bigger engines, I suppose.





KJ: "The prototype Tu-144 was shorter, featured a simple double-delta wing, a 5-abreast fuselage (thicker than the Concorde)..."

I did see that on drawings of the plane. No area ruling. The engines had to be big to overcome this inefficiency.




KJ: "...and two paired engines so close to each other that it looks like it's a single four engine box from some angles.

Yeah, sort of like a B-70. This could have made the wing like a sonic-boom-rider like the B-70.





KJ: "The production Tu-144 was longer, featured a more complicated delta-wing design and a retractable canard with slat and flap to allow the elevons to droop as flaps."

This improved aerodynamic qualities on landings very favorably. Pilots were impressed. Before then, landings required care.




KJ: "Engines were spaced further apart but in rectangular-structures like before with two engines each."

Probably reduced drag as well. Wheels were still in the nacelles between the engines and I think they were artificially cooled against aerodynamic heating.




KJ: "It's the Tu-144D that could do Mach 2 performance without afterburner --...The difference was the engines. Although I'm not sure about the specifics of that. I've been told
-The engine was a turbojet, unlike the turbofans used on the previous designs.
-The plane used the NK-321 Turbofan
-The plane used a variable-cycle engine which was believed to be beyond the Russians capability in 1970 when they began development by US estimates.
I'm not sure which."

I only read one reference to those engines(many years ago) and it did indicated the pressure ratio and thrust was high enough to allow Mach 2 speeds without afterburner. I would logically think it was one of the newest military-style engines that became available then. NASA did some SST experiments(briefly) with the biggest Russian engines from a bomber and then the Tu-144 was capable Mach 2.4.
 

overscan (PaulMM)

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KJ_Lesnick said:
It's the Tu-144D that could do Mach 2 performance without afterburner -- To my knowledge the basic airframe was either the same or largely the same as the standard Tu-144. The difference was the engines. Although I'm not sure about the specifics of that. I've been told
-The engine was a turbojet, unlike the turbofans used on the previous designs.
-The plane used the NK-321 Turbofan
-The plane used a variable-cycle engine which was believed to be beyond the Russians capability in 1970 when they began development by US estimates.

I'm not sure which.

I'm not sure where you get your information from, but its pretty well known what engines were used on the Tu-144D.

It used the RD36-51A turbojet. This was technically quite similar to the Olympus turbojet on the Concorde.

When NASA leased a Tu-144D a few years back for SST tests the RD36-51 was long out of production so they used the NK-321 turbofan as the only engine in the right size and thrust class.

The engine was a
 
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Lee

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overscan, quoted: "I'm not sure where you get your information from, but its pretty well known what engines were used on the Tu-144D. It used the RD36-51A turbojet. This was technically quite similar to the Olympus turbojet on the Concorde."

It was, indeed, according to:

http://www.tupolev.ru/English/Show.asp?SectionID=148&Page=2

RD 36-51 had a takeoff thrust of 21000kg(44,000 lbs). SFC = 1.23 kgf/kg h at cruise compared to 1.65 kgf/kg h at cruise for the NK-144 (pg.3 of this webpage at smallest font on landscape print).
Supersonic thrust and fuel consumption was better for the new engine and predicted by the Russians to be even more impressive with further development.


overscan: "When NASA leased a Tu-144D a few years back for SST tests the RD36-51 was long out of production so they used the NK-321 turbofan as the only engine in the right size and thrust class.
The engine was a"(sic)

Typo at the end of the message? Nevertheless, I thought they used, and I'm pretty sure Aviation Week said, the engines would get the TU-144 to Mach 2.4 to provide data for R&D of the next generation SST.
That was the reason for using them.
 

overscan (PaulMM)

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No, the reason for using them was as I stated. The RD-36-51 was long out of production with no spares. Coincidentally, using NK-321 did raise top speed, but that wasn't the reason for it.

I'm not convinced it would get to Mach 2.4 without afterburners though.
 
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Lee

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overscan, quoted: "...NK-321 did raise top speed, but that wasn't the reason for it.
I'm not convinced it would get to Mach 2.4 without afterburners though."

Okay, you're right. The NK-321` did come from the Backfire. Here's the reference:

http://aviation.ru/Tu/144/story1/ASM_T144_ON95.html

I just forgot the NK-321 came from that exact Russian bomber but the article I remember reading said the Americans wanted the biggest engines available to simulate conditions pertaining to the "high speed civil transport" (HSCT).
The Russians agreed, but possibly reluctantly. The CIA and NSA are well known by an informant of mine that they're fond of gaining information by any means possible, including planting extra black boxes or additional hardware hidden in the usual hardware to download engine parameters by mechanical sensory means way advanced of even anything I know.
I agree with you, though. The Backfire engine was the one they used and the one I remember. It couldn't maintain Mach 2-2.4 on the TU-144 without A/B, either. You're right about that.
 

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