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MPH or KTS?

MPH or KTS, Which do you prefer?

  • MPH

    Votes: 74 23.1%
  • KTS

    Votes: 247 76.9%

  • Total voters
    321
Mark - I don't know about you but I've never reported my position as 180MPH East of anything. At least not yet.
 
good grief... call it ft/sec, nanometers/millisecond or whatever you want and it will have ZERO relevance on how the airplane flies or how well it can be flown. As long as the plane has a nifty pink card from the FAA it will always have an equal place in aviation despite the assertion otherwise. OUT

In the good ole US of A you can call it what you want, BUT in the Aviation Community of the US of A we use knots. OUT
 
I thought 100kts = 115mph.


Yes, sorry for the confusion. I fixed it. My brain was thinking 100mph = 160k/hr.
All the more reason to find one unit of measure and stay with it. Standardize everything.:D
 
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I use MPH in my RV8 and my BD4 for no other reason than I like it. It is different from certificated airplanes, airlines, the military and any others who feel it has to be their way or the airway. It reminds me my airplane is special because I built it, can change it if I want, and am free as bird to do so to my liking. Its a bit more grass roots which is appealing to me.

US of A aviation uses both knots and MPH whether you chose to accept it or knot. :)

How about a new set a threads:
How should we measure Gross Weight, Kg or Lbs? fuel, L or gal? Altitude, M or FT? Temp, C or F?

Spanky
 
Bill,
I do not believe that anyone would endorse what you hypothesize in your posting. From my perspective, I would just like everyone to be on the same page for position and WX reports. The standard measurement is nautical for WX, ATC, etc., so it is just matter of safety and clarity.
Quite frankly, I don't believe that anyone cares what you use for your personal pleasure. If the bigger numbers give you a warm fuzzy...have at it. But I for one (and ATC too, I am sure) would appreciate it if everyone used the standard nautical scale for all reporting.
"Thats all I have to say about that"...F. Gump

Ditto , Ditto, Ditto, Use Knots
 
the knots have it

Now can we let this poor horse rest in peace?

Bet let me hypocritically pile onto the salesmen among you. Who ever decided that a KB was 1000 bytes... Total insanity, to any thinking person, but pure genius to hard drive salesmen; that ploy pays back at about 2.4 percent every few years... A little like the mph but sort of more like an annuity....
 
Non debate.

How about a new set a threads:
How should we measure Gross Weight, Kg or Lbs? fuel, L or gal? Altitude, M or FT? Temp, C or F?

Spanky

This is all a non debate,
The only debate is whether to conform to Standards or not.
Three nations have not officially adopted the International System of Units as their primary or sole system of measurement: Burma, Liberia, and the United States.
http://en.wikipedia.org/wiki/International_System_of_Units


Pete.
 
Your debate.

;) We don't have to, and you can't make us!

Cheers

Absolutely.
Every country that accepts the SI did so of free choice and equally, I respect the sovereign right of the USA not to accept them.
Why on earth would I want to make you? It's your ASI.

I was merely pointing why you are having the debate over knots & mph.

Cheers,
Pete.
 
Mixing Systems

You would all hate the airplane I did my commercial training on.
CHT, EGT and oil temp were in farenheit
oil pressure and fuel pressure were in kPa
the fuel gauges and fuel flow were in litres
fuel weight and weight & balance were pounds and feet.
ASI was knots and kph [some of the fleet was just knots]
altimeter and VSI were feet.
 
knots is definitely the standard!

even here in europe :)

km/h for speed and meters for altitude is only used by the gliders.
eastern block/chinese countries still use altitude in meters but apparently even some of them think about switching to feet as everyone else uses.

all the planes with mph remind me of a '57 chevy ;-)

rgds bernie
 
This is all a non debate,
The only debate is whether to conform to Standards or not.
Three nations have not officially adopted the International System of Units as their primary or sole system of measurement: Burma, Liberia, and the United States.
http://en.wikipedia.org/wiki/International_System_of_Units


Pete.

... which has nothing to do with aviation.

The ICAO is the world wide "standard" when it comes to aviation. The standard units are Feet and Knots. Not meters or kph.
 
I chose mph simply because it was what both my planes had and it's what I'm used to.

1969 PA28-140
1965 mooney M20C

Yep, both oldies :)
 
Mark: Thanks for your response. I was being semi-serious, but saw some tendencies to be very rigid and thought that's a lot like FAA thinking. Can't put much beyond the reach of bureaucrats! Frankly the tendency to regulate everything we see today is frightening to me. I grew up with mph and like 'em. That said, I've dealt in knots with ATC for 40 years and always use that unit when talking to them and nm when defining a position. The desire to standardize is understandable but look what's happened with the efforts to bring decimal units to the US...... hasn't really gone far despite a lot of effort. Does this suggest we really need the regulators to make it happen? I prefer to think when it becomes truly important we'll self regulate. I know there are VFR only RV's out there with ASI markings in mph. Maybe they don't need to change as long as their mission doesn't. Just hope everyone will be reasonable and not try to force their opinions on others who hold different views which are not causing problems. When we talk about flying to members of the public who don't fly, mph are more understandable than knots. The discussion has been interesting. Thanks again.
 
All the same speed

Does not matter what units since the speed is the same.
I usually use 165 kts for cross county planning but I could use
84.88 m/s
305.580 km/h
278.49 ft/sec
1,002,559 f/h
189.9 mph
0.247 Mach

I still get there in the same amount of time.
Quote what you want just make sure you always use the units.
 
Does not matter what units since the speed is the same.
I usually use 165 kts for cross county planning but I could use
84.88 m/s
305.580 km/h
278.49 ft/sec
1,002,559 f/h
189.9 mph
0.247 Mach

I still get there in the same amount of time.
Quote what you want just make sure you always use the units.

You forgot about 1.65 Mock.
 
Metric Altimeter

I had a chance to fly a glider once with a metric altimeter, now that was quite usettling as I wanted to take every thermal due to the "low indicated height", and my brain had a hard time cross referencing what I saw out off the cockpit with the position of the hands on the altimeter. As far as knots and mph I prefer knots purely for what I am used to, but also fly aircraft with mph ASI's. One thing that I'm not to keen on is dual scale ASI's as I think that they are rather cluttered. I would prefer either one or the other as a single scale. I got caught out once reading mph as knots in the cct as the work load went up at an unfamiliar airport with a very short runway in an aircraft that I had not flown before. Recognised it on the downwind leg as I had set up the landing configuration and approach speed early due to the the unfamilarity of the aircraft and airport, but it could have been a different outcome on finals. Statisically I bet other people have been caught by this as well. I pay close attention to dual scale ASI's now.

Bar Humbug winter weather is fast approaching

Happy flying
Rob
 
I'm late to this pity party, but I'll put in my two cents' worth. I did my military time; did time/heading/airspeed calculations ad infinitum. Don't need to do that any more - AOPA flight planner tells me the only two things I need to know:
a. Can I make it in one hop?
b. How long will it take?

Beyond that, it really doesn't matter what unit of measure you use.

I use mph for several reasons:

1. When my wife flies with me, she always compares our progress to driving to the same place in the car - she doesn't know or care why Knots are different, she wants to know mph.
2. Ditto everyone else who flies with me save the few who are pilots.
3. I use my 496 in my plane and in my car. I don't want to have to switch units of measure every time I transition between earth and sky.
4. Since I'm not going to switch my 496, I want everything else to read the same.
5. This is an experimental airplane, and until they regulate this freedom away too I can and will continue to use whatever I want.

Reasons AGAINST using mph are pretty much silly:
1. I know my cruise speed in knots. It never changes, and it's what I put on my flight plan and report to anyone who asks. If for some odd reason I vary my speed and HAVE to report it in knots, I can multiply by 7/8 in my head. It's never happened.
2. For the once in 5 years that someone actually asked me to maintain a particular speed, they simply asked how slow I could go. I know that speed in knots, too. It never changes.
3. For any other purpose, it really doesn't matter what units you display your airspeed in. You will still not get there any sooner.

Now, I'm not against any of you using whatever unit of measure you prefer. I consider it a triumph of our freedom that we can all employ a measure of anarchy in the air yet still be safe. I particularly like "Mock" and "furlongs per fortnight!" I wonder if we can get the EFIS makers to allow custom units?

:D
 
Knots vs MPH

Man, this one has been as good as the discussion of tail dragger versus nose roller.
I think I will start using the Mock scale. Normally, I cruise at 1.55 Mock. If I am in a hurry I will pick it up to 1.6 Mock. :D
 
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