h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

first off, the S-37 is not a production model, it's a technology demonstrator. second, it's not very stealthy, because there are right angles all over it and it has no radar or infrared shielding on the rear end. not that the f22 does, but anyway
where's the mention of stealth ships and helicopters? the french navy has a class of frigates that have stealth measures, and there's the RAH-66 comanche stealth helicopter.
and last but not least i've read a story somewhere of a sports car that had a body made of composites. this made it stealthy enough to speed by police radars unpunished.

Interesting, obviously I've been out of the loop for a while.

Some mention of the limitations of stealth would be welcome, particularly the fact that an aircraft becomes progressively more unstealthy as the atmospheric humidity increases, so don't fly through any clouds

Another aside, the first attempt at stealth on aircraft was the application of RADAR absorbent paint on existing airframes. Implementation was (as far as I know) limited to Soviet aircraft between 1943 and 1948, the first aircraft to be routinely 'stealthed' were Ilyushin Il-2 strike aircraft. Soviet policy changed with the introduction of large numbers of jet aircraft being introduced into service as 'nightfighters' were no longer effective against them, however it is possible, even reasonable, that with the introduction of RADAR-homing missiles the practice was resumed. I have never read of such a thing, but then it is exactly the sort of thing that might have happened.

That sports car would be the Corvette. It is somewhat stealthy, but the fact that the body is composites is only part of the story. One of the major radar return surfaces on an auto is the radiator. The radiator on the Corvette is angled at 45 degrees from the horizontal, which directs radar return energy away from the receiver... much the same way the F-117 does.

Don't you love it when someone drifts along two years later and comments on your comment...

The Lotus Europa was fiberglass, but had a huge radar cross section - I checked it once. Assumption was the radiator, great conductor, broadside to the acquiring signal. Perhaps the Corvette would be better, if the radiator is angled, but I have friends who can attest to the susceptability of the Corvette to Texas Highway Patrol radars...

Er also,

While the Sukhoi 37 has canard foreplanes it does not have a forward swept wing.

Forward swept wings generally need to be made of carbon fibre reinforced composites to avoid one of two unpleasant consequences:

1. The wing is unfeasibly heavy, compared to a normal wing

2. The wing twists itself off at high speed.

erm yes it does...

http://www.airforce-technology.com/projects/s37/

its just the newer model that is based on the s4/37 that doesn't

Regarding the engines, it's probable that it's carrying engines from a regular Sukhoi whilst they do aerodynamic tests on the bodyshell; witness the Eurofighter Typhoon prototype with the same engines as a Tornado fighter until the EJ200 was perfected on the drawing board.