CMP riddle #003

Hanno Spoelstra · #1 23-01-10, 15:33

Quote:

Originally Posted by Hanno Spoelstra

Let's start a new* game: CMP riddles!
*) IIRC we did play this game earlier, possibly on the old forum?

Yes we did, it was called quiz time!.

For answereing the riddle Why were the windows of the nr. 13 cab slanted inwards?, I grant Keith Webb 5 points.

Quote:

Originally posted by Keith Webb
To quote from Bart's Observer's fighting vehicles P. 212:
" The new cab had reverse-slope windscreens to reduce glare and also to prevent the piling up of snow, slush, etc."
Another reason was for blackout convoy driving so the driver could see the pinspot tail lamps of the vehicle ahead without reflections.

Close enough ... this is the answer I was looking for:
"The windshield slants forward placing the surface of the glass square with the driver's line of vision to the road and reduces the possibility of reflected light interfering with the driver's vision. It is exceptionally effective during blackout operations. "
Source: Ford instruction book Special Pattern Vehicles (third edition) p. 208.

Phil Waterman · #2 23-01-10, 23:35

I remember this coming up in the CMP '84 seminar, answers given as I recall reflect no one reasons. Among the reasons given and discussed:

Sun reflected on a closed windshield would reflect toward the ground and not back to an aircraft.

That dirt and snow tend to fall off which is good because the windshield wipers were marginal at best. Quite frankly most of the time you don't need the wipers in even heavy rain.

The angle of reflected light from the inside when driving under blackout conditions was better because it put the glass perpendicular to the viewing path from the drivers eyes to the area actually lit by the blackout headlights. I doubt this one as I have driven my vehicle extensively under black out conditions it works for following another vehicle but if you are the lead vehicle you want the windshield open all the way.

I suspect the first two are the real reason for the reverse windshield, either that or the designers took a perverse pride in creating a very distinct vehicle.

Cheers Phil