[robby0707]

Originally Posted by aim120

In that picture the SU30 has test missiles. So it must be a test for the flight control system with full weapons. Possibly simulating some failure.

We also don't know what fuel level is in the wings. If one side is heavy with fuel, the TVC nozzle could be compensating.

The missiles in the pic are all Russian dummy missiles (generally black rings indicate this) which are all already tested for the entire flight envelope of the aircraft. And it is carrying only 5 of them which is less than half the max capability (Wikipedia says it can carry 12), so nothing special to test again. The fuel( or any expendable material) is always kept equal in both sides if the aircraft so that the CG is always near to the center. balancing with the use of TVC is only possible for short periods because TVC can be effective only when the engine is producing a lot of thrust, that is when in its highest settings and therefore this is not a practical way of balancing the aircraft. Any asymmetry in any axis is always managed by aerodynamic forces.

[arijitkanrar]

Originally Posted by robby0707

While the Su 30 MKI is a TVC capable aircraft, the image above shows single engine switched off. Other wise, both the nozzles would have been deflected to the same direction( the position of the canards shows that the aircraft is not in a high AOA situation wherein TVC would be used). Also, while the SU 30 can manoeuvre in 3D using TVC, the nozzles does not move in full 360 degree. The just move up and down. The 3D manoeuvering is achieved by the axis of this movement being offset wherein both the nozzles trace a V shape. Thus, synchronous movement results in 2D mano( up and down) and asynchronous movement results in 3D mano( sideways). Also the image in which the aircraft is on ground and the nozzles deflected in opposite direction shows the Fly By Wire test going on. The nozzles are never deflected like that while in air.

Are you sure about the thrust vectoring part that the nozzles always move together?
The whole purpose of twin plane thrust vectoring is to generate thrust moment in all the three axis (roll, pitch & yaw). For this differential movement of nozzles will be necessary.

For e.g. for a faster roll to the right, the right nozzle would point up and left nozzle would point down generating a rolling moment.

Here is a video that shows how twin plane nozzles move. Watch the initial parts where the Sukhois are shown.

https://www.youtube.com/watch?v=U7Nsko6bvC8

[sagarpadaki]

Originally Posted by arijitkanrar

https://www.Youtube.com/watch?v=U7Nsko6bvC8

Wow. It looks like a ballerina in the sky, the way it turns and rolls at such slow speeds!? Is the Su30 MKI also capable of such dance moves?!

I do not know if such manoeuvers have any use in real combat situations.

[robby0707]

Originally Posted by arijitkanrar

Are you sure about the thrust vectoring part that the nozzles always move together?
The whole purpose of twin plane thrust vectoring is to generate thrust moment in all the three axis (roll, pitch & yaw). For this differential movement of nozzles will be necessary.

For e.g. for a faster roll to the right, the right nozzle would point up and left nozzle would point down generating a rolling moment.

Here is a video that shows how twin plane nozzles move. Watch the initial parts where the Sukhois are shown.

https://www.Youtube.com/watch?v=U7Nsko6bvC8

Yes. What i meant when i said that the nozzles move only in one plane is that one single nozzle moves only in a straight line. Now this movement is offset ftom the vertical by an angle of approx 35 degrees ( wikipedia) inwards which make both the nozzles trace non parallel paths unlike that of a raptor which has nozzles that move only vertically up and down. Thus the raptor cannot induce a force to the side ways using the TVC and has to use the rudders for this which makes it capable of 2D super manoeuvres only where as the tilt trick of the nozzles of the MKI makes it possible to exert a force vector sideways which makes it capable of doing 3D super manoeuvres. The TVC are practically useless for roll as the torque (the distance from the axis of rotation and the force exerted is called the moment arm and the torque exerted to roll the aircraft will be directly proportional to the moment arm) from the ailerons will always be greater than the TVC is as they are very closely spaced together ( as you can see in the video, the aircraft is hardly rolling). Also the tilt in the nozzles further aggravates this problem because now only a factor of the total thrust is exerted in the rolling. Above all that, roll alone is a useless manoeuvre except for displays. Unlike cars, aircraft cannot move sideways. They can move only up and down and the purpose of roll is to make this up and down movement sideways so that the aircraft can turn. Now in the MKI, if you have seen displays, you’ll find the the 3D TVC enables the aircraft to move sideways while staying flat. And therefore at low speeds this is used for sideways turn.

[locusjag]

Originally Posted by sagarpadaki

Is the Su30 MKI also capable of such dance moves?!

In a similar vein, does Sachin know how to hit a silken smooth straight drive ? Aircraft from the flanker family (Su 30 MKI included) are highly manoeuverable. Very, very much so.

I do not know if such manoeuvers have any use in real combat situations.

The Western press says this is all good only for airshows and grabbing eyeballs. Their playbook depends on BVR warfare, jamming etc., more than WVR dogfighting. But conversely, their F22 has comparable manoeuverability; they wouldn't develop such a capability in their frontline aircraft if it were totally useless.

[ads11]

Originally Posted by locusjag

The Western press says this is all good only for airshows and grabbing eyeballs. Their playbook depends on BVR warfare, jamming etc., more than WVR dogfighting. But conversely, their F22 has comparable manoeuverability; they wouldn't develop such a capability in their frontline aircraft if it were totally useless.

IIRC The F-22 vectoring is only along one axis (up and down essentially), not the full rotation that the nozzles on the Flanker series have for eg. I'm not well placed to say just how much TVC contributes to the manoeuverability of these jets, especially the F-22 because it manages to achieve it without having that full spectrum vectoring like a Flanker.
A lot of the airshow tricks though aren't moves that get executed in combat, despite how awesome it might look so I do think that the truth lies somewhere in the middle when it comes to TVC.
Out of upcoming aircraft I know the demonstrator for the Japanese 5th gen X-2 has 3 paddles to vector thrust, who knows what will make it to the final design. Not as sure if the Koreans have it on the KF-2 prototype and I certainly don't remember seeing it on the Su-75 mockup.
Besides, the F-22 is out of date. The last clean sheet design, the F-35 did away with vectoring nozzles altogether (obviously with the exception of the F-35B which needs to rotate the nozzle downwards for STOVL).

Re the playbook, aren't most air arms converging on engaging at stand off ranges? It seems only natural that you'd rather not get up close and personal with the adversary, preferring instead to do so as early as possible.

[robby0707]

Originally Posted by robby0707

Yes. What i meant when i said that the nozzles move only in one plane is that one single nozzle moves only in a straight line. Now this movement is offset ftom the vertical by an angle of approx 35 degrees ( wikipedia) inwards which make both the nozzles trace non parallel paths unlike that of a raptor which has nozzles that move only vertically up and down. Thus the raptor cannot induce a force to the side ways using the TVC and has to use the rudders for this which makes it capable of 2D super manoeuvres only where as the tilt trick of the nozzles of the MKI makes it possible to exert a force vector sideways which makes it capable of doing 3D super manoeuvres.

Originally Posted by ads11

IIRC The F-22 vectoring is only along one axis (up and down essentially), not the full rotation that the nozzles on the Flanker series have for eg. I'm not well placed to say just how much TVC contributes to the manoeuverability of these jets, especially the F-22 because it manages to achieve it without having that full spectrum vectoring like a Flanker.
A lot of the airshow tricks though aren't moves that get executed in combat, despite how awesome it might look so I do think that the truth lies somewhere in the middle when it comes to TVC.
Out of upcoming aircraft I know the demonstrator for the Japanese 5th gen X-2 has 3 paddles to vector thrust, who knows what will make it to the final design. Not as sure if the Koreans have it on the KF-2 prototype and I certainly don't remember seeing it on the Su-75 mockup.
Besides, the F-22 is out of date. The last clean sheet design, the F-35 did away with vectoring nozzles altogether (obviously with the exception of the F-35B which needs to rotate the nozzle downwards for STOVL).

Re the playbook, aren't most air arms converging on engaging at stand off ranges? It seems only natural that you'd rather not get up close and personal with the adversary, preferring instead to do so as early as possible.

Check out my previous post for differences between the TVC of a raptor and the MKI. As of the effectiveness of these manoeuvres, these are quite effective in a visual combat with older missiles having lesser field of view which required the nose of the aircraft to be pointed to the nose of the other aircraft as much as possible and not to that extend in today. As we can see, both the Raptor and the MKI were conceptualised in the 90’s ( Raptor even before that).

[dragracer567]

As mentioned earlier in this thread, HAL will apparently go forward with the procurement of 6 used Boeing 767s for conversion into mid-air refueling tankers using expertise from the Israeli company IAI which has done a similar conversion for the Colombian Air Force. To that end, HAL will float a global tender for the procurement of used 767s. As with defense contracts in India, the saga with the procurement of mid-air refuelers in India has been going on for a while now with the A330 MRTTs being selected multiple times but then being rejected everytime for being too expensive. The IAF has been looking to get some A330 MRTTs on lease as well including one from the French Air Force but we aren't sure if this approach has been abandoned either.

Another interesting point in the article is that the IAF is apparently looking at the feasibility of converting the Air India 747-400s that has been de-registered by the DGCAs into military cargo aircrafts. The conversion of 747 passenger aircraft into cargo planes is pretty common though not for a military role. I remember reading that the USAF has explored this as well long back before backing off! I am guessing that there is a gap in heavy-lift capability after the C17 production got shut down, but I am not sure how useful a 747 cargo plane would be for the military. Can they carry armored vehicles and tanks? Also, can they land in airfields like the Leh airport?

[skanchan95]

Originally Posted by dragracer567

Can they carry armored vehicles and tanks? Also, can they land in airfields like the Leh airport?

It is probably not possible for a 747 Freighter to carry tanks & APCs but they can carry light military armored vehicles.

I remember that the National Airlines 747-400F that crashed in Afghanistan almost immediately after take off was carrying 4 or 5 MRAP vehicles on board. Those vehicles were not secured properly and it led to at least one vehicle moving rearward as the aircraft pitched up for take off. It damaged the aircraft's hydraulic systems and the horizontal stabilizer components, which rendered the airplane uncontrollable, causing it to crash.

[Jeroen]

Originally Posted by dragracer567

Can they carry armored vehicles and tanks? Also, can they land in airfields like the Leh airport?

Yes at least in theory. At 10.000 feet altitude and a 9.000 feet runway you can land a 747 no problem. However, there is different problem, weight. The amount of cargo (and fuel) you can take with you, or take off, comes down drastically at higher altitudes.



In order for a 747 to actually land at Leh, lots of things would have to be considered and maybe adjusted/altered too. One of the certification requirements would be the fire surprising capabilities. It doubtful that Leh’s current fire department is equipped to handle a 747 crash landing with fire. Also, things like wingspan and whether you can actually taxi around the field without hitting is a factor.

Fields are approved per aircraft type and Leh, to my understanding, is not approved for the 747. Also, I seem to recall pilots landing/taking off have a special endorsement? But of course, all of my limited knowledge is based on civilian operations, military operation might be different. although, some of this stuff is related to physical measurements and performance. That does not change for civilian versus military operation.

Jeroen

[ads11]

Originally Posted by dragracer567

Another interesting point in the article is that the IAF is apparently looking at the feasibility of converting the Air India 747-400s that has been de-registered by the DGCAs into military cargo aircrafts. The conversion of 747 passenger aircraft into cargo planes is pretty common though not for a military role. I remember reading that the USAF has explored this as well long back before backing off! I am guessing that there is a gap in heavy-lift capability after the C17 production got shut down, but I am not sure how useful a 747 cargo plane would be for the military. Can they carry armored vehicles and tanks? Also, can they land in airfields like the Leh airport?

Are there many extant examples of converted civilian 747s being used for military airlift? To my mind it could only really be for moving personnel and palletised loads of goods between logistical bases. I doubt it's the kind of platform that could be used in a FOB. For the USAF I can still see them finding utility moving from one major logistics hub to another hub closer to the theatre from where other aircraft ferry the goods to where its needed but how much of this is necessary for the IAF?

If the primary utility for the IAF heavy lift component is being able to access the furthest forward bases, what are other existing heavy lift platforms that have undergone trial within India? Are there any that could make the cut in the absence of the C-17? It's not quite an apples for apples comparison but wouldn't the A-400M be the next closest analogue for this capability? (Not that Airbus have any luck when it comes to Indian procurement).

[sagarpadaki]

Slightly offtopic, do the IAF jets have the name of the pilot painted at the base of the canopy like the western jets do? From whatever pics I see, I do not see the pilots name anywhere on the airframe

[dragracer567]

Originally Posted by ads11

Are there many extant examples of converted civilian 747s being used for military airlift? To my mind it could only really be for moving personnel and palletised loads of goods between logistical bases. I doubt it's the kind of platform that could be used in a FOB. For the USAF I can still see them finding utility moving from one major logistics hub to another hub closer to the theatre from where other aircraft ferry the goods to where its needed but how much of this is necessary for the IAF?

I am guessing that one of the major applicants of the C17 is indeed to move palletized goods between various hubs. For example, based on media reports, I believe Chandigarh airport is a major hub for goods that get transshipped (not sure if that's the right term here) to Ladakh. So, I am guessing that by using the 747s for this role, the C17s can be reserved for more specialized roles such as for carrying tanks, paratroopers or to carry goods into airfields like Leh (or even smaller airfields) which based on Jeroen's assessment seem unlikely to be able to handle a 747 practically. I am guessing all this will be taken into account during the feasibility study. And offcourse, given that this is just in the feasibility stage, it is more than likely that this won't pan out. Also, if this is the case, the IAF might as well hire commercial cargo 747s like the USAF as skanchan95 pointed out.

If the primary utility for the IAF heavy lift component is being able to access the furthest forward bases, what are other existing heavy lift platforms that have undergone trial within India? Are there any that could make the cut in the absence of the C-17? It's not quite an apples for apples comparison but wouldn't the A-400M be the next closest analogue for this capability? (Not that Airbus have any luck when it comes to Indian procurement).

You are right, the only analogues to the C17s are the Il-76MD-90A, A400M and the Chinese Y20. But what differentiates the used 747s from these aircraft is the cost. These 747-400s are more than 20 years old with the oldest being almost 26 years old. If they aren't taken in by the IAF, they will have to be retired since they have been deregistered already, so it's likely that the IAF will be getting these aircraft at throwaway prices. The major cost will likely be the conversion and OPEX cost for such old aircraft, not the purchase cost. There is still the question of how much longer you can keep using a 20-26 year old aircraft without safety concerns though (again probably will be answered by the feasibility study)! Also, aren't these the same aircraft that were converted and used on a need basis to be used by the Indian head of state and government for foreign travel?

[skanchan95]

Originally Posted by sagarpadaki

Slightly offtopic, do the IAF jets have the name of the pilot painted at the base of the canopy like the western jets do?

This was allowed by the IAF before 1999. There are pics of IAF jets with pilot names painted under the cockpit and on the nose. This was discontinued after the Kargil War when nearly all IAF jets switched to all grey paint scheme and the squadron logo painted on aircraft were not allowed too. However, a few squadrons did continue to paint their aircraft with low-viz squadron logos but pilot names are a strict NO.

The Indian Navy on the other hand, never disallowed such practice. So even now their aircraft, especially MiG-29Ks fly with squadron logos and pilot & technician names painted under the canopy (USN/RN style).

[dragracer567]

Sticking with transport airport, Embraer is apparently in talks with India to sell its C390 Millenium aircraft. I'm guessing these are just preliminary discussions that might not actually pan out since I'm not entirely sure where the C390 will actually fit in. The C390 has a higher payload capacity as compared to a C130J Super Hercules though I think the Hercules is physically bigger and can carry more troops. Given that India already operates the Hercules, makes more sense to buy more of these. One interesting capability of the C390 is to function as a mid-air refueller while it shares its engine with the older A320 CEOs which can simplify maintenance.



The C390 looks strangely similar to our own ill-fated HAL MTA / Ilyushin Il-276 which was supposed to replace our An-32s (I'm guessing these will eventually be replaced by Indian-made C295s).