I don’t think one can generalise the BPR ratios as being indicative of engine’s application for instance

BPR of some typical engines

GE Engines

F110-129 – F16 C/D Block 5x models
BPR = 0.77
Thrust dry/ab = 76/129 kN
Stages = 3+9+1+2

F404-402 – F18 C/D Models
BPR = 0.27
Thrust dry/ab = 53/79 kN
Stages = 3+7+1+1

F414-400 – F18 E/F Models
BPR = 0.4
Thrust dry/ab = 56/98 kN
Stages = 3+7+1+1

P&W Engines

F100-229 – F16 C/D Block 5x & F15E
BPR = 0.36
Thrust dry/ab = 79/129 kN
Stages = 3+10+2+2

F119 – F22A Models
BPR = 0.45
Thrust dry/ab = 105/158 kN
Stages = 3+6+1+1

Klimov RD-33 – MiG 29
BPR = 0.49
Thrust dry/ab = 49/82 kN
Stages = 4+9+1+1

Lyul’Ka AL-31FP – Su 30 MKI
BPR = 0.65
Thrust dry/ab = 83/142 kN
Stages = 4+9+1+2

SNECMA M88-2 – M2K
BPR = 0.3
Thrust dry/ab = 50/75 kN
Stages = 3+6+1+1

Clearly the BPR ratios for P&W and GE engines are vastly different. Yet they produce about equal amounts of thrust with approximately the same tsfc for the same model aircraft which logically should be used for the same application.

The pressure ratio, mass airflow and number of stages within the engine are more relevant to the performance and thence the application of the engine.

eg

comparing the GE 110129 to the P&W 100-229 we can observe the following (GE : P&W)

BPR = 0.77 : 0.36
Thrust dry/ab = 78/129 : 79/129 kN
Pressure ratio = 31 : 32
Mass airflow = 123 : 116 kg/s
Stages = 3+9+1+2 : 3+10+2+2
Weight = 1790 : 1698 kg
TWR dry/ab (engine only) = 4.5/7.7 : 4.8/7.9
dia = 1180 : 1181 mm
lenght = 4630 : 4855 mm

Ken,

Thanks. In that photo you posted , those ‘pointy’ things look very similar to the speared ends of the pistons which engage the water-brakes.

Indian,

IIRC the problem IMO was never the design of a catapult. If you can make a steam engine you can make a decent steam launcher. The problem was the design of an arresting system for the “after aircraft disengagement” braking of the pistons. The braking system has to be robust enough that so it can brake the piston along with a fully loaded aircraft from 160+ knots to zero if the aircraft fails to disengage.

In the USN and Brit carriers they use/d a horizontal chamber of filled with water. This was kept filled using centrifugal forces. Once the speared end of the pistons entered the water brake, the water pressure acted to stop the pistons. Keeping enough water under pressure to maintain safe braking ability was / is the main issue with current naval catapult design IMHO.

I suppose with the new EM cats braking will also be by means of EM power or do they still want to use waterbrakes?

On the proposed MiG 23 K – any idea if the dual ventral fins were present – if present were they folding or fixed as shown in the naval variant redesign of the MiG 23 A?

Is that an IRST fixture forward of the redesigned 23K canopy? Any chance of a 3view line drawing of this proposed variant?

Were the catapults steam powered?

Originally posted by SD-10
Unfortunately China does not have a third world country in sight

to show its latest technology on them.

How typical – make wild unsubstantiated claims. Then when asked to prove it – make unrelated comments about unrelated topics.

Just to bring you back on track:

You said :> PLAAF would not have developed a plane which in any way inferior to LAVI, F-16 MIG 29 and Su-27 in flight performance.

I asked you :> It is a little frustrating to see people make claims about flight performance based on what they feel is right. SD-10 support your claim with numbers not your hunches.

And you reply with the gibberish above. I ask you substantiatte your claim – do not make grandious claims if you cannot back them wth data.

I see uncomfortable queries are flames in your mind?

Just asking a harmless question. It doesn’t make you uneasy though – this business of being a Pakistani and being forced to post under an assumed identity?

Pity!

Originally posted by Arthur
So it has been done on this airframe.

Not sure if you are asking a question or making a statement?