Astra BVRAAM

[PaliwalWarrior]

is 27g enough ?

 

[Bheeshma]

How many g's can a fighter aircraft pull?

 

[SajeevJino]

How many g's can a fighter aircraft pull?

I think, Most fighter Aircraft are designed to survive upto 24 G's . but Pilots are able to perform only 9g's which is safer to human Body. Exceeding the Limit may cause severe damage to the Human Body

 

[power_monger]

I think, Most fighter Aircraft are designed to survive upto 24 G's . but Pilots are able to perform only 9g's which is safer to human Body. Exceeding the Limit may cause severe damage to the Human Body

For every G pulled by Aircraft missile needs to counter it by multiple G's to outbeat it. 24g's is generally not good enough to defeat a fighter with good pilot.

 

[Khagesh]

For every G pulled by Aircraft missile needs to counter it by multiple G's to outbeat it. 24g's is generally not good enough to defeat a fighter with good pilot.

I do not know as a fighter pilot but merely the input of 27 g that was mentioned by the reports is clearly insufficient detail. The report inputs provided are more intended to flummox people who rely on Brochure data too much. So if somebody says that an AIM120 can do this and that kind of ta-ta-thaiya then DRDO has just said we can too. And thats it.

What evasive maneuvers, what accelerations, what turn angles are involved has not been said.

However the 27-40 G that is getting talked about, I 'feel' should be enough. Because the Astra would be decelerating towards the outer part of its stated range and would definitely be lighter, so I guess it would not need to pull as many g forces. Astra Mk-1 should be able to turn with the targeted aircraft, as good as any other similar BVRAAM. A BVRAAM need not necessarily turn like a WVRAAM. A short range AAM has to turn even when it is accelerating and turn faster (even backwards) and at the same time it may not be in as good a position to extract the best mileage from the proportional navigation as employed at longer ranges by BVRAAMs. That is why both kinds have distinctive designs optimized towards a particular type of challenge that the other simply does not have to face.

The best way to read the report, that again I only 'feel' is that we allow the testers the benefit of intelligence and presume that when they say that they tested against a 'simulated target', it implies that they did their math right, in terms of turns, accelerations, sensor covers, kinematics edge of performances. Because unless we cast doubt on their intelligence there is no way we can doubt the test as a success with the data we have.

Like for example:
Merely because Astra has achieved 27 G we cannot presume that 27 G is the upper limit achievable. So the report is a piece of understated propaganda (which is what I 'feel'); and
Merely because they have stated the range as X does not imply that X range is with a petered out performance (which I what i 'feel' again)

That is why, I 'feel' we can presume that they have the kinematic spare capacity of Astra in their favour for the realistic engagements.

 

[sayareakd]

is 27g enough ?

Good start for development flights.

 

[power_monger]

Khagesh,

There are lot of factors. Firstly the pilot will fire a series of missiles to attack the opponent jet fighter. So although 27G might not be theretically enough to destroy opponent fighter jet,it is more than sufficient if fired in multiples.And we have just stared with version 1. Once we receive more and more data,the missile can be fine tuned and it can be deadly weapon in 4-5 years(It is almost deadly now).

we need to work incrementally to achieve the best. There is no single route to achieve the so called best.BTW, Astra was planned to perform 40G maneuvers at sea altitide.What is not known is whether 27G performed by Astra was good enough for the simulated electronic target or it it has potential to reach the targetted 40G capability at sea level with better target maneuvers.

 

[PaliwalWarrior]

Good start for development flights.

i am not criticizing but aking for my own knowledge

also what should be ideal g values i should achieve to be a sure shot deadly missile ?

 

[sayareakd]

i am not criticizing but aking for my own knowledge

also what should be ideal g values i should achieve to be a sure shot deadly missile ?

More the better, target is 40g. You see they have to set up special test range where all these G have to be recorded not only by fighters, missile, target but also by ground stations.

This is first attempt, so 40g is good if you take that 9g is human limit and pilots pass out for lack of blood in brain.

 

[DivineHeretic]

More the better, target is 40g. You see they have to set up special test range where all these G have to be recorded not only by fighters, missile, target but also by ground stations.

This is first attempt, so 40g is good if you take that 9g is human limit and pilots pass out for lack of blood in brain.

Sir, while the numbers you have stated is undoubtedly correct, you are missing the actual meaning and import of the numbers. One needs a reasonably good concept of Newtonian Physics to make sense of these numbers.

The 40G for the missile does not necessarily equal better performance than the 9G for the fighter aircraft. I could try explaining the nuances but it'd long, and boring. And I suspect most people will fall asleep while reading

 

[power_monger]

Sir, while the numbers you have stated is undoubtedly correct, you are missing the actual meaning and import of the numbers. One needs a reasonably good concept of Newtonian Physics to make sense of these numbers.

The 40G for the missile does not necessarily equal better performance than the 9G for the fighter aircraft. I could try explaining the nuances but it'd long, and boring. And I suspect most people will fall asleep while reading

perhaps you can give it a try.I will bookmark it and read it whenever i dont get sleep.

 

[Bheeshma]

The Python-5 itself can only do 45g so 40g is a very good start.

 

[SajeevJino]

Sukhoi snag hits Astra testing ​

The crash of a Su-30 fighter in Assam and a snag in another of these aircraft worry the Defence Research and Development Organisation (DRDO) as the trial of its beyond-visual-range air-to-air missile, Astra, against a simulated target from the Integrated Test Range in Odisha could not be conducted on Tuesday.

Following the snag on Monday, DRDO missile technologists postponed the trial to Tuesday.

Senior DRDO scientists told The Hindu that spare parts for the aircraft were being flown in. The efforts needed for an air launch were more than what was required for a ground launch.

Referring to the crash, a senior scientist said normally the Indian Air Force would ground all Su-30 aircraft in the wake of an accident to find out “if it is a common problem”. He said the DRDO team would await clearance from the IAF to conduct the trial. Three trials spread over two to three days would be conducted as the missile would be released at different altitudes. High manoeuvrability of the aircraft would be looked into during the trials.

http://www.thehindu.com/todays-paper/tp-national/article7225123.ece

 

[DivineHeretic]

perhaps you can give it a try.I will bookmark it and read it whenever i dont get sleep.

This site was blocked(?) or perhaps refused connection on our college network, by which I mean the Central government's fibre optic network and hence I was unable to gain access to it for a long time. This is why the reply is so late.

When we talk about acceleration, we typically mean linear acceleration. This is your

However, when we talk about the peak acceleration of aircraft and missiles (and anything that does not move in a straight line), we talk about the second type of acceleration, the angular acceleration .This is given by
http://data:image/png;base64,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

Where v = speed of the object & r = radius of curvature of the path followed by the object at a particular moment.

Now that we have the fundamental equation, let’s explain the meaning of those G-numbers.

I’ll use three values of acceleration: 9G corresponding to a normal fighter AC, 12G corresponding to absolute maximum human endurance, and 40G, corresponding to a modern AAM/SAM.

(G means the acceleration due to gravity = 9.81 m/s2)

I’m attaching the following graph to help explain what these numbers mean. I’ve made it simple so that anybody can use it, as I’ll demonstrate in the following example.

Let’s consider a fighter jet and an AAM. Now, to survive, the fighter jet must be able to make a sharper turn than the missile. In short, the object with the smaller radius of curvature (i.e. tighter turn) wins, every time.

Now the fighter jet travels at the speed of 330 m/s, or Mach 1 and has a maximum G limit of 9G, while the missile travels at 1500 m/s, or roughly Mach 4 and has a G limit of 40G. (you can use your combination of numbers if you like)

Now, from the graph you can see that the Radius of curvature for the aircraft is around 1200 m (1233 m to be exact), while that for the missile is roughly 6000m (5733 m to be precise). This means that even though the missile is faster than the aircraft and has a higher G limit, the aircraft will comfortably evade the missile in a turn. The aircraft wins.

In fact, the missile will have to fly at less than 700 m/s to have any chance of striking the aircraft.

This is why despite what a lot of people might believe, evading a missile is not impossible.

I hope the explanation has been adequate. If not, feel free to ask, or correct me if there’s any flaw.

[/url] imgupload[/IMG]

 

[power_monger]

Astra missile sucessfully fired when the fighter jet was performing a “very high-g manoeuvre”


DRDO scientists plan to conduct another trial on Thursday to prove the long range capability of the missile.

After postponing twice, the indigenously-developed beyond visual range air-to-air missile, Astra was successfully launched from Su-30 MKI fighter jet in two developmental trials conducted at the Integrated Test Range, Chandipur, Odisha on Wednesday.

In the first trial, the supersonic missile was released when the fighter jet was performing a “very high-g manoeuvre”. In the second trial, the manoeuvre was higher than in the first exercise.

A Defence Research and Development Organisation (DRDO) missile technologist told The Hindu that extreme conditions were simulated for the missile’s launch in both the trials when it was released at very low and very high altitudes. DRDO scientists plan to conduct another trial on Thursday to prove the long range capability of the missile.

With Wednesday’s tests, seven developmental trials were conducted and the missile is expected to be inducted by 2016 after few more tests, including pre-induction trials.

Once inducted, India would join select group of nations which possess this kind of stat-of-the-art weapon, said the scientist. He said it is the first state-of-the-art air-to-air missile developed and validated by DRDO. “It is one of the most modern, stand-off beyond visual range air-to-air missiles (BVRAAM)”, he added.

The 3.8-metre tall Astra is a radar homing missile and one of the smallest weapon systems developed by DRDO.

Various laboratories of the DRDO, including the missile complex at Hyderabad, CEMILAC and DGAQA collaborated with Hindustan Aeronautics Limited (HAL) and the Indian Air Force in developing Astra.

 

[power_monger]

T

In fact, the missile will have to fly at less than 700 m/s to have any chance of striking the aircraft.

This is why despite what a lot of people might believe, evading a missile is not impossible.

I hope the explanation has been adequate. If not, feel free to ask, or correct me if there’s any flaw.

[/url] imgupload[/IMG]

Do you mean to say missile should slow down to mach 2 to hit aircraft trying to evade at 9g?

 

[DivineHeretic]

Do you mean to say missile should slow down to mach 2 to hit aircraft trying to evade at 9g?

Precisely. Everything else being the same, the slower the speed, the tighter the turn. You might have seen in F1 race, where the driver coming in too fast can't make a tight turn, and is sent off the track. It follows the same principle.

In the case of the missile, the path of the aircraft is it's track, and if it cannot slow down sufficiently to stay in track, it will overshoot. And therein lies the problem: Very few missiles have variable thrust, that would allow it to change speeds.

 

[power_monger]

Precisely. Everything else being the same, the slower the speed, the tighter the turn. You might have seen in F1 race, where the driver coming in too fast can't make a tight turn, and is sent off the track. It follows the same principle.

In the case of the missile, the path of the aircraft is it's track, and if it cannot slow down sufficiently to stay in track, it will overshoot. And therein lies the problem: Very few missiles have variable thrust, that would allow it to change speeds.

If this is so obvious,Do you think DRDO would have factored this into the missile?
BTW,do you know examples of other AAM which uses this variable thrust?

 

[cobra commando]

Astra missile fired from Su-30 MKI again

In yet another achievement in two days, the indigenously developed air-to-air supersonic Astra, was successfully fired from Su-30 MKI fighter aircraft and tested for a very long range at the Integrated Test Range, in Odisha on Thursday. On Wednesday, two Astra missiles were launched when the fighter aircraft was performing high-g manoeuvres in two separate trials. According to a Defence Research and Development Organisation (DRDO) missile technologist associated with Astra project, the anti-aircraft missile on Thursday climbed to an altitude of 25 k.m. and went to a very long range after it was released at an altitude of 25 k.m. He said that the weapon system was evaluated under extreme conditions. The control and guidance and all other sub-systems were validated at very high altitude and range as the missile zoomed at a speed of 4.5 Mach in the eighth developmental trial held on Thursday. After a few more pre- induction trials, the supersonic missile is expected to be inducted by next year. The 3.8 metre tall Astra can carry a warhead weighing 15 kg and intercept and destroy enemy aircraft at supersonic speeds in head-on and tail chase modes. It possesses high Single Shot Kill Probability (SSKP) and can be launched from different altitudes.

Astra missile fired from Su-30 MKI again

 

[DivineHeretic]

If this is so obvious,Do you think DRDO would have factored this into the missile?
BTW,do you know examples of other AAM which uses this variable thrust?

It should be kept in mind that some of the most 'straightforward' problems require the most complicated of engineering solutions. Conversely, some of the most 'complex' of problems have been solved with some of the most simple engineering solutions.

Having said that, Astra has a dual pulse rocket motor. Quoting from bayern-chemie :The key characteristic which the dual pulse motor design enables is the capability to manage different thrust impulses according to mission need. The pulse management is achieved through the use of dual propellant charges separated by a frangible bulkhead, where the charges can be ignited separately.

Performance Characteristics include:

• No signature during coast-phase
• Active motor impulse control on mission demand
• Increased kinematic performance in endgame
• Avoidance of high peak velocities
• Increased range especially against highly manoeuvering targets

Technology:

• 2 separate propellant grains for two pulses in one motor case
• Pulse separation by passive frangible bulkhead
• Dual independent ignition systems

Bayern-Chemie are the developers of the propulsion of the MBDA Meteor AAM. And as you might have guessed correctly, the Meteor is another AAM that has variable thrust.

ASTRA's propulsion is indeed a very very important milestone for us, and yet it somehow doesn't find a special mention in most of the news reports about it.