Posted on 10/22/2007 8:03:29 AM PDT by sukhoi-30mki
India and Russia sign fifth-generation fighter deal By Vladimir Karnozov
India has finally talked Russia into giving it equal funding and engineering shares in the next-generation fighter to be developed jointly by the two nations.
A co-operation agreement on joint development and production of the fifth-generation fighter was signed in Moscow last week. This follows the general agreement reached during Russian president Vladimir Putin’s visit to New Delhi in January.
A key point of disagreement had been India’s stance that both sides be equally responsible for funding and engineering. Sukhoi argued that Russian designers had been working for five years, making it hard for India to catch up.
Sukhoi’s position prompted India to seek co-operation with RSK MiG. Since the MiG project was less developed that Sukhoi’s, it was easier to reconcile the positions. Also the new MiG I-21 was lighter than Sukhoi’s T-50 and closer to Indian requirements.
But the Indian side agreed in January to accept Sukhoi’s T-50 as the basis for the jointly developed fighter. The decision comes four years after Russia selected the T-50 over the I-21 as its next tactical fighter. Sukhoi plans to fly a prototype in late 2008 or early 2009.
Moscow and New Delhi plan to create a joint venture, similar to that for the Russian-Indian BrahMos cruise missile. Four working groups will study workshare and timing details.
Sukhoi sources say the Russian company agreed to the 50:50 principle, but India has promised that, if its industry is unable to provide its share on time, the Russian partners will be invited on commercial terms to help India catch up.
Why does it look like the F-18?
MV
I give up - why?
My turn
Why does the F-18 look like the F-15?
Why does it look like the "Firefox" that Clint Eastwood flew?
The F18 does not look like the F-15 any more than it looks like the
F14 save for the twin tails and the swept wing.
The F-18 specifically has out-angled tails. Note the design
of the tails on the SR71 (tilted inward slightly) vs that of the
F-14/15 (straight up). The F18 twin tails are angled outward
by perceptively more than a few degrees.
In fact, the tails on the F22/F35 look to have even greater outward
angle than the F18.
Why do you suppose the trend is toward increased outward angling of the twins? Hmmmmm. Greater stability about the yawing axis perhaps.
MV
It looks like they took the tail and fuselage from the forward-swept Su-47.
I think the Russian designs are cool, but they keep rehashing older designs into “new” aircraft and claiming a new generation.
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Oops.
Didn’t notice the subtitle.
At least my instincts are good, if not my reading comprehension.
There are scores of CG images of the Sukhoi 5th Gen fighter-all claiming to be accurate & looking similar to a variety of planes from the SU-30 to the F-22 to the F-35!!!
I believe the F-14 vertical stabs have an outward cant also. Only the F-15 stabs are vertical.
Prevent dutch rolls at low speed.
I’ve seen many of those, which is why the Su-47 based drawing was confusing. They cannot extend this platform into a true Fifth Generation aircraft if it’s origins are explicitly current generation.
Looks like the vert stabilizers have a very SLIGHT outward angle.
Hard to pick up from a straight-on shot unless you are looking
for them.
However, the config appears closer to the F15 than the F18.
I expect the aerodynamics to be quite similar in the case of the
F14 and F15 in terms of vert stabilizer qualities. OTOH, the outward
pitch is pronounced on the F18 and even moreso on the F22/F35.
Obviously, a twin tail config offers some advantage; otherwise,
it would not have been incorporated by various manufacturers
over the last 40+ yrs. Furthermore, the outward angling of the
tails must also offer an advantage.
MV
You mean like the F-22, F-35, MiG-29, SU-50, F-117, Firefox, etc?
Aircraft designed for similar roles by different entities will have many similarities, due to the irrefutable laws of aerodynamics.
That does NOT mean they are copying each other, just that they all realize that the most efficient wheel is round.
Low speed Dutch Roll? Most a/c are well-damped wrt/ DR at lower
speeds are they not?
Does the angling outward of the twins function in a yaw-damping
role?
In a comparative analysis of the F14, 15 and 18, the F14 is by far
a giant at 45K lbs. The F18 is a veritable runt at 24K lbs. Moreover,
as expected wrt/ powerplant considerations, wingspan of the14 is
50% larger than that of the 18 assuming that I have used like figures
for each a/c. The 18 is shorter than the 14 by about 7ft.
Perhaps the lighter weight of the 18 lends itself to poorer yaw damping
qualities at higher (or lower????) speed necessitating the greater
stability afforded by the outward angling of the twins. The 14 can also
swing wing, which can increase/decrease surface area as well as altering
the sweep. Trade-off here it seems. Lift considerations vs drag issues.
Tell me more about DR at low speed.
MV (inquiring minds)
See my post #13.
A/C may or may not “look” that much alike depending on what aspect
you are looking at. The GENERAL appearance of the F14, 15 and 18 from
a profile perspective will all look pretty similar. Then when you
realize that one is much larger than the other two etc. Or when you
realize that the wing config on one is somewhat diff from that of another,
etc.
The F22/F35 do not look like the F18 and earlier twin tail class a/c.
They do however, have the twin tails and the swept wing.
Twin tails and the swept wing are not new concepts. The P38 Lighting
of radical design was a twin tail/twin fuselage a/c as were a number of Brit
WWII a/c. Esp the bigger a/c such as the Lancaster. The Lockheed
Connie was also a multi-tail a/c. Three I think if memory serves.
Additioanlly, the F106 Delta Dart was a swept wng as was the F102
DDagger.
No, my question was sarcastic. It is in the same vein of that raised
by another Freeper earlier this yr wrt/ everything the Russians roll
out looks EXACTLY like what we rolled out but 10yrs earlier. Same
goes w/ the space shuttle.
MV
You have to take in aspect ratios and wing surface along with slipstream affects by the fuselage and the vortex lines pushed down the plane. Most of it is above my head. My pilot/engineer dad told me about it.
The angle also diffues radar reflectivity.
Re radar reflectivity. I agree w/ that re the F22 and F35.
But the F18’s outward angle is not sufficiently large to diffuse
reflectivity effectively esp as the plane. although pretty small
compared to the F14 lacks stealth. She still offers nice surfaces
from which to capture effective radar bounce.
Yeah, wing surface area. The F14 is able to alter its surface
area based on how much of a sweep it took on given the
situation.
The vortex lines you speak of are assoc w/ the fluid (air) flows, right?
You are not talking about the stress lines, eg, the Leui lines, that
appear in the structure due to the incident forces.
MV
Vortices of the fluid air flows yes. I am not familiar with aspects of the stress lines and their air stream disruption.
At lower speeds they need a higher angle of attack to do lower profile wings and that causes move disruption down the fuselage as it becomes less aerodynamic with its belly exposed to air stream and envokes a waffling/settling effect.
Yaaa, so the angling outward not only increases stability about the
yawing axis but it lessens the effect of “tail wagging”. That is Dutch
Roll = yawing + wagging.
I knew there was a phenomenon of “tail wagging” in which at certain
speeds, the tail section looked like it was actually wagging. And
it seemed to me that from the video I saw, it was a matter of time
before the tail wagged itself off. I cannot recall the name of this
phenomenon. I believe it has something to do w/ aeroelasticity
of the structure/materials and the hitting on of a certain frequency
of vibration. It was an unbelievable sight.
Of course, this ‘wagging’ occurred in the vertical plane and not the
yawing plane.
MV
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