That ‘bit more than mach 1’ was actually M1.21.

Source AFM:-
And its reported that one Rafale programme insider grudging said about the supercruise “they didn’t wait for a cool of the evening, they didn’t wait for a cooler day, – they just went out and did it in a hot daytime tropical environment” .

At the same time a hotter environment means less dense air! Hence the speed of sound is lower and the mach value is higher!!! :diablo:

Is there any reference in that article on the tradeoff between its engines’ higher efficiency at lower temps. vs the lower speed of sound at higher temps.?

Thanks.

They’re parked – not on the flightline.

g load

Here’s a way to calculate it

g-load = 1 / COS (bank angle)

If you can observe the angle that the arm rises from its perpendicular position you will be able to calculate the g force involved.

A guide

59.99550488 deg = 2 g
70.52984949 deg = 3 g
75.52399438 deg = 4 g
78.46309023 deg = 5 g
80.40522358 deg = 6 g
81.78670721 deg = 7 g
82.81924020 deg = 8 g
83.62061558 deg = 9 g
84.26083238 deg = 10 g
84.78410354 deg = 11 g

and onwards till at a 90 deg bank you will experience 1.63 e+16 g of force.

Hope that helped!

If a NEO is in danger of striking the earth we would have only 2 choices (obvious, but restated to establish base position).

a) destroy the object so that its debris is small enough to burn up in the atmosphere and/or the remaining pieces are not large enough to cause extensve devatation even if they don’t burn up.

b) change the trajectory of the object far enough away that it misses the earth.

destroy object

Nuclear weapon
How much force would you require pulverize an object about a km in size – current megaton nukes should be able to manage the jobs. The only problem with this is the nukes would have to be set off on the surface of the object or within the blast radius of the warhead. In vacumn in the absence of an atmosphere to multiply and carry blast effects the nukes would have to be very very powerful and set off within the blast radius of the warhead. For larger NEO you would require larger or multiple warheads set off simultaneosly.

LASER
In theory it is possible to produce a laser whose power is not significantly derated while travelling through the atmosphere. But clouds, humidity smog etc. do not guarantee this. Therefore you would need a space based laser. The problem is then how do you power this laser for a long time? The small nuclear reactors we have managed to get into space do not produce sufficient wattage to enable long distance coherency of the beam and have sufficient power at the end to make a difference.

change orbit
For an object to be a NEO it has to be travelling at-least 42,000 m/s or more in the vicinity of Earths orbit. (that is the escape velocity of the Solar System at Earths orbital distance). If it was travelling any slower it would never have reached Earth orbit instead it would have swung into solar orbit and be captured as a satellite of the sun.

Rockets to divert trajectory
If you want to use rockets to divert the trajectory you would need a very large rocket running for a very very long time to create enough momentum for a trajectory change. And I mean very large even the Russian proton boosters burning for less than ~1000 secs is not going to make a difference to an object whose size is Earth threatening.

Else you would have to do it far enough away that it would make a difference. Even then you would probably need very many boosters to make a difference. Then you have the technical problem of getting those heavy objects into space and redevous wth the object. Current tech does not allow for it – therefore large powerful rockets are out.

Nuclear weapons
Is what may make the difference – let off enough of them close enough to the object and far enough away during its approach and you may just be able to make a deg or 2 of trajectory change. More than enough given the distances involved.

JMHO

likely true

Re: Re: How much do the Russians know about USAF aircraft?

Originally posted by flex297
To achieve much better aerobatics shorter turbofan engines were needed. Soviets came with the Tumanskiy RD-33 twin-spool turbofan, greatly inspitred by a stolen technology of MTU Turbo Union Rb-199 (yes, EAP and Tornado).

The turbo union RB199 is a 3 spool turbofan laid out in the 3+3+6+1+1+2 configuration. The Rd33 is a 2 spool turbofan laid out in the 4+9+1+1 configuration. Both of them were certified and entered service around 1980. The rb199 has a BPR of 1 the rd33 has a BPR of ~.4. I really can’t see what exactly they copied from the rb199?

I don’t believe you can get your inspiration from an engine which is under development and still manage to get yours into service around the same time as the engine you are copying from. Specially if your copied engine only has the LP and HP stages and the engine you are copying from has LP+IP+HP stages. I mean whats the point of copying from a 3 stage engine to make a 2 stage engine? What is the advantage of that? Those are 2 completely different engines.

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added later: Ooops aerospacetech beat me to it by a long shot 🙂