tjt@kobold.UUCP (T.J.Teixeira) (11/30/83)
When measuring for a first down they mark the place where the chain
intersects one of the lines that cross the entire field every 5 yards.
This point is used as the reference point when the chains are moved
across the field to where the ball is.
There could be a problem making the chain perpendicular to the yard
line. This could be done by eye, and if it is that close, you could
swing the chain slightly: it is perpendicular when it is farthest away.
Five degrees of error at five yards is less than an inch and only
rarely is the measurement that close.
Of course, the whole idea of measuring first downs to that sort of
accuracy is pretty ludicrous given how the ball is placed anyway.
--
Tom Teixeira, Massachusetts Computer Corporation. Westford MA
...!{ihnp4,harpo,decvax,ucbcad,tektronix}!masscomp!tjt (617) 692-6200zzz@mit-eddie.UUCP (Mike Konopik) (11/30/83)
I agree that it seems pretty bogus to measure without having first established that the yard markers are supposed to be RIGHT THERE to begin with. It would make loads of sense to bring in the chains and put the clip on the chain at the nearest 5-yard mark (as they do when preparing to bring them in for a measurement) and then take them to the sidelines. The only (and a very big) drawback is that this sort of thing would take a LONG LONG TIME, and would interrupt the momentum of a game where there is, say, 1 minute left and the team behind just threw a 20-yard pass to put them into a scoring position... And measurements generally happen very rarely, so the interruption isn't too annoying. Teams would only tend to bitch and moan when they're disputing whether the offense crossed that established line or not, not when they just made a first down... -- -Mike genrad!mit-eddie!zzz (UUCP) ZZZ%MIT-OZ@MIT-MC (ARPA)