Where Tejas falls behind

[Irfan Baloch]

Oscar is the man to answer this, however....
Could it be to help the pilot in downward weapon sighting visibility, had the wings continued with the 45 degrees, the pilot would be oblivious to the ground environment unless he tilted the aircraft......just my two cents. ???

I agree that the wing it self is very big already, had it continued with the same angle it would have pretty much engulfed the whole fuselage.
now that I think about it. your assumption makes perfect sense. this angle though, does present some aero dynamic challenges but it seems to be a reasonable trade off due to already big wing which must be giving a lot of lift here.

 

[MilSpec]

del .............

 

[Lazarus1177]

About 1 billion.

Is this the cost of the total project or does it exclude the cancelled engine which was planned to be made in India?

 

[MilSpec]

the most prominent or characteristic feature of this plane is the shape of the wing near the fuselage.
if the angle of the wing from the edge is (for example 45 degrees) then as it nears the fuselage it suddenly takes a dip to a 60 or 70 degrees.

what is the significance of that shape and design? there must have been a lot of debate over doing it. but I cant find anything on web

what are your thoughts? what did the designers plan to achieve with this (sorry for the lack of word) radical design

any thoughts, any comments or theories?

sir,
I believe it's to achieve optimal balance between low aspect ratio and lift/delay. the desired size constraints led to this design, if the length of the fuselage was longer, and conventional cranked arrow could have been used, but to get the low wing loading, this was the best choice, other option would be canards which would need additional software and control system. This serves the purpose.

 

[Abingdonboy]

Is this the cost of the total project or does it exclude the cancelled engine which was planned to be made in India?

The Kaveri was de-linked to the LCA prgram some time ago. The Kaveri hasn't been cancelled merely ADA have concluded they will not use it from the get go on the LCA MK.II that had been envisioned. The engine is still being developed for other uses such as marine engines and could still be fitted to LCA later during the LCA's MLU.

 

[Irfan Baloch]

Source:From B_R's tsarkar:

I get the design but I am asking why it was taken?
pitches the nose before the stall at higher? AoA? hmm dont get it must read up more to understand what that means lol totally different territory

so in essence canard is merged with the delta wing?

interesting. now I must look up cranked delta concept and reasons to adopt it if I dont get the answer then I will ask again.

 

[BATMAN]

sir,
I believe it's to achieve optimal balance between low aspect ratio and lift/delay. the desired size constraints led to this design, if the length of the fuselage was longer, and conventional cranked arrow could have been used, but to get the low wing loading, this was the best choice, other option would be canards which would need additional software and control system. This serves the purpose.

The other way around could be to add some fuselage! That may have served the purpose better!

 

[Windjammer]

With most aircraft as with this Mirage-2000, wings usually attach to the fuselage behind the canopy and with the likes of F/A18, the pilot still has good look down ability.

 

[MilSpec]

The other way around could be to add some fuselage! That may have served the purpose better!

Could have been, but the IAF guidelines were to keep it certain size and weight, in retrospect, they could have made smaller su30 tupe a/c but ADA followed IAF's directive to make an optimal Low cost, light fighter.

 

[ramu]

LCA is not the first to have a cranked Delta wing.

 

[Kompromat]

LCA has almost 90% identical wing area to that of SAAB viggen.

 

[Pak47]

LCA has a very bad aspect ratio..
It's major flaw is it produces less lift in relation to drag

 

[BlueDot_in_Space]

LCA has a very bad aspect ratio..
It's major flaw is it produces less lift in relation to drag

how?? do you have any data to support your claim??

Tejas has relaxed static stability with stability augmentation and blended wing/body.

Relaxed Static Stability advantages
– Increases lift-to-drag ratios at subsonic and supersonic speeds
– Reduces down-load on the horizontal tail required to trim at high lift
coefficients and at supersonic speeds
• Increases total lift available at sustained-turn conditions

• Blended Wing/Body
– Provides additional volume for fuel storage, increasing range
– Reduces wetted surface area, reducing drag
– Increases structure rigidity

so in essence canard is merged with the delta wing?

yes in a way you can say that.

 

[Paan Singh]

Awesome contribution frm every body..

 

[acetophenol]

Nice to see such genuine discussions are back in pdf! Carry on guys!

By the way,whats the endurance, i.e, how many minutes can Tejas stay airborne with maximum fuel( internel +3 drop tanks) and ammo,with internel fuel alone, and how does it compare with others?