Completely agree with you .Not everyone is blessed with common sense.
I am sorry to say that what you have suggested is sure shot recipe for disaster like LCA. We must know each and everything which we want to fit into the aircraft before hand. The design must satisfy the needs of internal space to house all the avionics and fuel volume. After you decide the size of the aircraft, you should go for aerodynamic analysis. My concept is based on off-the-shelf avionics already operational. This gives me the advantage to know before hand the exact dimensions of every equipment which goes in my aircraft and decide the shape and size of it. Once the design complies with the goals, we should go for detailed CFD and wind tunnel testing of the design. The final design must also comply with take off and landing speed and field length required requirements including desired ITR and STR values. LCA was supposed to land at speeds below 230kmph or 130kts but it lands at 307kmph or close to 165kts. Why such a big difference in the ASQR and final product?
AMCA is another disaster in making as the final configuration for line flying has not been decided and we do not know what additional kind of avionics we will have in 2030. In fact we do not even know where to fit which equipment to finalise the final line product. many of you post comments of some very high ranking test pilots from LCA program. I talk to them at will. In my last chat with them I questioned what their motive is in making an AMCA TD and if they have designed it from inside out or outside in like LCA. They had no clue of it. I asked them have you decided how you will ensure 360* coverage of sensors? all they could tell me was that they will think about it once the TD is made.
Regarding Naval AMCA, more than anyother service, Navy needs internal bays and very large amount of load carrying ability. Please go thru what happened in vietnam. The largest amount of load was delivered on target not by F-4 phantoms but by a small single engine aircraft called A-4 Skyhawk. A-4 could undertake multiple mission and yet show up for duty whenever needed.
NAMCA will never happen. I have also studied the design and I can tell you that the TWR of the aircraft is far low, wing loading far higher, fuel volume too low and so unfit for operations at sea and from 66% of Carriers to be fielded by IN in 2030 time frame which will include Vikky+IAC-1 & 2. AMCA is purely an AF aircraft and not fit for IN. NAMCA will be able to go with good load only from a CATOBAR carrier.
200 meters is too few.
SA2 (which has a quite big warhead) destroyed fighters at this distance during Vietnam war.
500 meters seem better.
The forum is think tank forum, which involves in brain storming,
You can have common sense then you are best to get a bean counting job or, if you do have desire to be on the forum try and contribute on threads that are common sensical as per you, best not to use the space for threads where you dont see common sense.
Thank you
You can have common sense then you are best to get a bean counting job or, if you do have desire to be on the forum try and contribute on threads that are common sensical as per you, best not to use the space for threads where you dont see common sense.
Thank you
We did wait for Kaveri for Tejas,, is it still available ? So what is HAL going for ? Its going for GE F-414..
So, you can think that we can get Kaveri... if it manages to evolve,
Further Kaveri and F-414 and most other engines are not the engines for 5th Gen engines
so we need to get tech like that available for Item 30 engine, else AMCA will be a 5th Gen plane with 4th gen engine, which is still 4th gen plane.
So, you can think that we can get Kaveri... if it manages to evolve,
Further Kaveri and F-414 and most other engines are not the engines for 5th Gen engines
so we need to get tech like that available for Item 30 engine, else AMCA will be a 5th Gen plane with 4th gen engine, which is still 4th gen plane.
First, I never said that the size is completely unimportant. I only said that the general size is first decided but exact size depends on aerodynamics. It is obvious that one begins with an estimated size as the MToW can vary from 13ton to 40ton in an aircraft. EVen twin engine ones can vary from 20tons to 40tons. Obviously an estimate of size is required. But exact size is always dependent on aerodynamical shape. The landing speed test etc are indeed needed but the airframe limits come only in high speed landing. Low speed landing requires control surfaces like canards to break the speed. Tejas had a problem as it has no proper control surface and is also a delta wing plane which requires higher speed for flight stability. This is not a universal case and must not be generalised.
How is this relevant? Do you know what is internal bays? The stealth fighter has internal bays to accomodate the payload inside the plane and hence to not increase drag or RCS by hanging outside. But the internal bays can hold only 1 missile or 2 PGM bomb. This means that the plane will have to carry extremely limited amount of payload if it has to work like a stealth fighter. So, to carry large amount of load, one must compulsorily carry the bombs and missiles in pylons on the outside of the airframe, not inside internal bays.
I also know that the requirement for carrier based aircraft is to drop large load. That is exactly why I am saying that the stealth part becomes irrelevant for carrier based operation. The internal bays are no longer needed for NAMCA but instead is better off being used to carry 1-2 ton more of fuel.
AMCA engine is not yet decided. If the engine is 110kN twin engine, then the TWR will be high enough. Also, the internal bays can be converted to fuel chamber to increase fuel capacity as I have mentioned above. Lower fuel capacity is only for stealth configuration, not for carrier operation. If the fuel tank is big, then the AMCA will become fat and non-maneuverable like F35 with internal bays
I did not even tell you the concept, why are you speculating the distance? Why are you in the habit to talk of something that you really dont understand? I think 200 metres is optimum distance for this Active protection system.
What you are talking of is the proximity fuse detonating the warhead and where the velocity of the moving missile also adds to the velocity of the frags and thus giving it a better range,
The concept here about the system is to hit the incoming missile and to destroy the missile or to try and divert the missile by the exploding "bomb"
BTW which air defence missile detonates 200 metre from a plane to destroy the plane? I do hope to know it.
What you are talking of is the proximity fuse detonating the warhead and where the velocity of the moving missile also adds to the velocity of the frags and thus giving it a better range,
The concept here about the system is to hit the incoming missile and to destroy the missile or to try and divert the missile by the exploding "bomb"
BTW which air defence missile detonates 200 metre from a plane to destroy the plane? I do hope to know it.
@Kshithij Sharma, I had a very long and heated debate with a test Pilot who showcased LCA in Bahrain air show. You guys know his name very well. I had this debate about Relaxed static stability (RSS) based on FBW and slight positive stability in fighter aircraft design. I do not want to tell you what happened at the end of debate. But will share some points here.
- A RSS aircraft achives stability by virtue of control surfaces and thrust line manipulation. The CG and metacentre height are very important in that aspect. nearly every RSS aircraft is low wing design which allows engine thrust to give a nose down movement and help achieve positive stability which is disturbed by the control surfaces.
- A positive stability aircraft can also use the same rules to achieve RSS in flight using CG, Metacentre height and thrustline. But the biggest advantage of such a positively stable design is that everytime you add a new weapon system, you do not have to write thousands of new software codes and prove them. A positively stable design in three axis with marginal stability has the advantage over RSS design.
- I shared my design with this head of Indian test pilot school and asked him how is my design inferior in agility and manoeuvrability compared to LCA or any such design when my tail plane is nearly neutral or providing positive lift during flight. For a normal stable aircraft, tail plane compared to a canard has negative lift called trim drag and that adds weight to the aircraft by reducing total lift.
- so just the way you need to give control inputs to keep an unstable aircraft stable. My design is stable and becomes unstable in flight. My thrust line is below the CG of my aircraft and that gives it nose pitch up. I control it by using my tail plane to give it a nose down moment which adds lift to my design and makes it superior to any canard design of the world. Rafale during fight at cornering speeds has a negative force generated by the canards to keep it stable. The vortex lift added by such a motion of canards has an effect of increasing the overall lift even with negative lift generated by canards. In my design, I have large Chine+LERX+BLC and positive lift from tail plane to more than out perform any canard design.
Thank you for those golden words . It was sorely needed .I actually took a screenshot , printed and laminated it and now keep it on my toilet flush . It's extremely inspiring .For appropriate endeavours. Please do provide more such pearls of wisdom .One never knows where might one need it.
I request you to read once again what I posted. In my very recent presentation to IN, I had a Cdr who was part of the team which wrote the RFI for Naval fighter. He was trying to be too smart for his size and rank. I asked him a few questions and he was looking like an idiot in the gathering. With even the Admirals present in the presentation telling him to keep quite as he did not know what was being talked and debated. Aerodynamics is hawabaazi. bahut muskil hoti hai samajhnay kay liyeh. And I have been a pilot since feb 1983.
Meri itni reputation toh hai kee aaj bhi IN & IAF main koi bhi mujhay question nahin karta aerodynamics main. What you have posted in in grossly wrong.
Its not about common sense its about they have never worked in any industry developing airframes or defence related avionics and here they talk as if they have designed the whole aircraft.
When I read these posts I feel they are wasting their time posting all irrelevant things. Not even close to what actually happens. Its just a time killing debate.
Kaveri is being readied and will be out next year. Kaveri is 4.5 generation engine with better TET than AL31F and slightly better TET than F404, mainly due to cooling improvement.
F22 internal bay is 3.9m length, 0.9m width and 0.35metre depth. But F35 internal bay is smaller and can carry 2 JDAm and 2 AIM9
I am not speaking of aerodynamics but the relative importance of aerodynamics wrt to size and internal configuration and the sequence of fighter jet construction. Aerodynamics and stealth property is the first thing that is evaluated with an approximate size in mind. Only after the right design is obtained, the right size is obtained. I don't know much about aerodynamics, but the sequence is something obvious. So, the lamenting that ADA is not taking Navy into account is simply a rant
This will be dangerous during take offs and landings when the shear is high and which may force pilot to control the stalling aircraft and the chances of crash landing or stall during take off increases.
Not going to happen in next 7-8 years make it 10. We are still not been able to have mastered material technology especially single crstal/tensile strength with rapid increase decreas in temperature and pressure of the material and surroundings.
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During take off it is not a a problem as the engine will be at maximum power and so the part of thrust adding to pitch up will be really high and once the nose is rotated for take off, the tail plane will add lift to give much higher lift for very quick acceleration.
However during landing, the thrust is going to be low and the pitch up available from engine thrust will be low while the pitch down by double slotted flaps, drooped aileron and BLC will create a much bigger nose down moment. To add to it, my design has fuel tanks on top of the fuselage which will result in lowering of metacentre height and cause the thrustline to actually give a nose down moment further compounding problems and adding to trim drag.
It is for this reason that i have my design come in to land with fuel in rear tanks to shift the CG further aft. This will help me to come to land with sufficient amount of drag requiring large amount of thrust which will add to the overall lift of the aircraft and also ensure that engines are sufficiently spooled up to an RPM which allows rapid acceleration to full afterburner thrust within 2.5 seconds as needed for deck ops.
Impossible. To carry 3xAMRAAM with 45cms wingspan in staggered configuration, you need at least a main bay size of 4x0.9x0.55m. The missile itself may fit within a square of 32x32cms but the clearance between the bay doors with bay door thickness and the height of the pneumatic launched also need to be taken care of.
That seems to be an experimental design especially when you have added the fuel tanks on top of the fuselage to have the canard stall first then the main wing in simple words. But then it's requires thorough tests during combat sorties and dog fights especially to study the chaotic dynamics of the fuel inside the tank and air flow during flights.
because normally you can't simply add fuel tanks anywhere on the fuselage to balance the aerodynamics. The placement of fuel tank would work well with the aerodynamics but then due to chaos in the fuel tank during flights the metacentre and CG would drastically change at different fuel lvl. Also the outside temperature of the fuel tank has an important role, in this design some coating would be required so that fuel doesn't freeze inside the tank due to water molecules present in tank and higher airflow over the fuselage. Or the tank heater has to intake the heat from engine or over work of the tank heater which adds up to the power consumption. Or sometimes the design of the fuel tank doesn't fit with the fuselage for a proper flow, even with the pumps.
You already know things get very complicated due to minute changes. But it's all to be tested. Can't prejudice any thing beforehand.