Larry,

Your assessment of the odds sounds pretty reasonable. I should probably have stated it the other way around, that if the chute is ever spotted, it would be worthwhile to look around for a relatively fresh crater. I think Hartmann mentioned something about the chute being rather large, I think he said ~100m or so, which was why it was credible to think that it could be found in a 20m/pixel Viking image. The "unusual" part had to do with the impact probably being slower than the usual natural impactor.

Mars-2 descended into a dust storm, which changes considerably the calculations for the distance the chute might have traveled.

The NSSDC profile on Mars-2 describes the spacecraft, and I noticed it mentioned a retrorocket pack ("the engine to initiate the landing") but no descent engine. This was to have been a hard landing, with internal cushioning, and the Soviet-style three-petal leaves that would open up and right the lander (shades of Pathfinder!). I'd expect the mission profile to want to keep the chute attached as long as possible, consistent with not letting it tangle--it should be relatively nearby the impact point.

On top of all that, it carried a rover ("Prop M"). They were way ahead of our time. Too bad they couldn't make it work.

I took a jump once, years ago. I was doing just fine, pulling the shroud lines according to the big arrow the ground crew was pointing to guide me in...too late, I realized they were guiding the guy who jumped before me. What with the plane's motion and the wind, their instructions were guiding me in to the neighboring cow pasture...complete with cows! I started yelling, the cattle scattered, I cleared a barbed-wire fence by inches, my feet landed in a slick cow patty and I hit the ground on my butt. But hey, any landing you can walk (or limp) away from is a good one, right?

Hanging in the air over the north San Francisco Bay a couple hours before sunset, dead silence except for the slight rustling of the wind in the lines...I whooped and roared like a maniac! That's an experience nobody can ever forget.

--Robert