VAF Forums - Knots or MPH?? That Is The Question

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- - Knots or MPH?? That Is The Question (https://vansairforce.net/community/showthread.php?t=81947)

To me a pace (having used it a fair bit in the field to estimate distance) is R-L-R, thus 1000 5-foot paces is pretty close to a mile.

Quote:

Originally Posted by gasman (Post 622977)

The average 6 foot tall male has about a 3 foot stride. In the example of a mile equal to a thousand Roman paces, their stride had to be 5' 3" long!! And YES.... that would require some very tall legs.

BTW......... How did the 201 Mooney get it's name?

Quote:

Originally Posted by DanH (Post 623056)

Hey, we decided this issue years ago, right here on VAF. Everyone was happy with the Mock System.

100 mph = Mock 1....cocktail party bragging rights for RV-12 owners.

200 mph = Mock 2....routine for the rest of us, although -9 owners really should fix their static system leak.

300 mph = Mock 3....used by a small group of Rocketeers, or the airport liar.

Dan,

don't forget the GAPHO system!

04 gph = GAPHO 1...cocktail party bragging rights for RV-12 owners

14 gph = GAPHO 2...routine for the rest of you

lbs/hr = GAPHO 3...used by a small group of Rocketeers.

(just having fun of course...not necessary to brag about gph at stall speeds)

Pete

You got a problem with that? See Above avatar from an 'ol carrier sailor in Naval Aviation...nuff sed...:cool:

Quote:

Originally Posted by Jerry Fischer (Post 623068)

You got a problem with that? See Above avatar from an 'ol carrier sailor in Naval Aviation...nuff sed...:cool:

Old carrier sailor? When I was in the Navy we still used oars. ;)

Real sailors deploy on destroyers BTW. We measured distance in strokes per hour. :D

;)

Quote:

Originally Posted by hydroguy2 (Post 622948)

I use Knots...but today I needed to do some bragging. So before work I took a short flight over the ice fisherman at the Annual Perch Derby. Zipped by them at 150agl(offset 350') doing 205MPH just to show them what 200mph looks like. At the end I pulled into a ~3000fpm climb.

Life is good at 178kts, but 205mph makes a better fishing story.

I'm surprised you would post such a thing in a public forum, potentially monitored by the Feds.

Quote:

Originally Posted by skylor (Post 623105)

I'm surprised you would post such a thing in a public forum, potentially monitored by the Feds.

150agl(offset 350')= 500'. That's legal, isn't it?

Quote:

Originally Posted by ccsmith51 (Post 623059)

All the reasons for using knots are valid. However, I use MPH because that is what every plane I have piloted since I started flying in 1968 has the ASI in MPH. I was instructed in MPH. I don't fly IFR, and the guys I fly with use MPH.

Does anyone know why, if knots is the standard for aviation (charts, ATC, ect.), it seems virtually all civilian aircraft made in the last 50 years have ASI's in MPH? It seems like the manufacturers should have used knots, but they didn't. Or would that be an option when the plane was manufactured and the buyers selected MPH?

I suspect that civilian airplanes had their speed in mph because the marketing whiz's thought faster speeds sold more airplanes. Somebody in an earlier post in this thread mentioned that it would be impossible to certify an airplane using mph, now. All the airplanes that were certified using mph probably still have a valid type certificate that used mph. Just a guess on my part.

Knots are the standard. (FAA, ICAO, etc) However, I think there are some countries that use metric routinely.

Quote:

Originally Posted by skylor (Post 623105)

I'm surprised you would post such a thing in a public forum, potentially monitored by the Feds.

150agl(offset 350')= 500'. That's legal, isn't it?

Looked it up, to be sure

(c) Over other than congested areas. An altitude of 500 feet above the surface, except over open water or sparsely populated areas. In those cases, the aircraft may not be operated closer than 500 feet to any person, vessel, vehicle, or structure.

Quote:

Originally Posted by rvmills (Post 623022)

So Larry, just how many buckets of popcorn have you enjoyed since stirring this pot up, eh!
Cheers,
Bob

Check your math Larry.....

So you are flying 350 ft laterally away from the fishermen and you are 150 ft above the ice. Thats a right triangle. The ''hypontenuse of that triangle is 381 ft. (Square root of (350 squared plus 150 squared). I'm no aviation expert, but I think 500 feet requirement is a straight line measurement.
I think you would have to be 476 feet laterally to the side of people at 150 ft to equal 500 straight line.
My guess is you are wagging the lateral distance and if you checked it closely you would see that you were indeed farther away than you estimate:). But thats just my humble opinion....