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jakethesnake214
08-09-2007, 09:37 PM
I was having a discussion with a friend of mine about the different speed bar modes in the game. He prefers knots because he is a real-world pilot and for obvious reasons he was trained in those units. I prefer whatever the instruments in the plane are so that if I fly in a server with the speed bar turned off I am used to the units for that particular aircraft.

My question is, why was feet and knots chosen for altitude and speed, respectively, as a standard in the US and the rest of world excluding a few regions which chose the metric system? And, when was this standard put into effect, considering that the American aircraft in game all use miles per hour for indicating speed?

Thanks in advanced.

berg417448
08-09-2007, 09:47 PM
For the US:

June 26, 1946--The Aeronautical Board agreed unanimously that the knot and the nautical mile be adopted by the Army Air Forces and Navy as standard aeronautical units of speed and distance, and directed that use of the terms be specified in all future procurement of air speed indicators, charts, related equipment, and future issues of applicable handbooks and technical orders.


US Navy aircraft were using knots prior to that date however.

The reason that they use knots is that the length of a nautical mile is almost identical to a minute of latitude. It makes measuring distance on a navigational chart easier by using the latitude indicators on the side of a chart.

OD_
08-10-2007, 03:20 AM
I think you will find it is standard in most places not just the US.
The UK also uses knots and feet. I was trained in knots and feet.

OD.

Viper2005_
08-10-2007, 04:22 AM
Knots became popular when aeroplanes started flying sufficiently long ranges that navigation became a serious business since it obviously makes it easier to work with most charts. Prior to that, statute miles were quite popular. Of course in naval aviation the need for commonality drove the move to knots much earlier than aircraft range would have done on its own...

As for feet, it just so happens that they were the accepted unit for short(ish) distances during aviation's formative years. I also suspect that the effective resolution of most altimeters in the early days would have been about 100 feet or so, which is a nicer number than 30 yards.

When I fly IRL I navigate in knots, but some aircraft (eg Cessna 150s) have ASIs calibrated in mph, and if that's the case then that's not a big deal really. For day VFR work you don't really need to know your ground speed in order to navigate since you're just bumbling along from landmark to landmark, so the ASI is really just a poor-man's angle of attack indicator...

In the game, partly because IL2C works in km/h and m, and partly because I fly blue quite a lot, I tend to work in km/h and m since this allows me to more easily compare my performance with that of my opponents. From time to time I must confess that I switch over to knots & feet and mutter "I wish the Robin would fly this fast/high"...

Skunk_438RCAF
08-10-2007, 06:10 AM
I like to read the gauges in the cockpits of the planes I fly. Most of the planes I fly indicate in knots and feet. The rest of my squaddies however are dependant on the speed bar. So for personal flying, I dont use it, but when flying with the rest of the squad, in order to have a universal unit I give them my speed in kilometers and altitude in meters.

MEGILE
08-10-2007, 06:22 AM
I like KPH, and FEET... go figure.

jakethesnake214
08-10-2007, 02:37 PM
Originally posted by OD_:
I think you will find it is standard in most places not just the US.
The UK also uses knots and feet. I was trained in knots and feet.

OD.

I said the US and the rest of the world minus a few regions.

Thanks for the replies guys. If I remember correctly, in-game the speed bar moves by a minimum of 10 meters, and minimum of 50 feet. If this is correct then the metters scale is more accurate because 10 meters is roughly 30 ft, therefore more accurate correct?

Taylortony
08-11-2007, 07:08 AM
Originally posted by jakethesnake214:
I was having a discussion with a friend of mine about the different speed bar modes in the game. He prefers knots because he is a real-world pilot and for obvious reasons he was trained in those units. I prefer whatever the instruments in the plane are so that if I fly in a server with the speed bar turned off I am used to the units for that particular aircraft.

My question is, why was feet and knots chosen for altitude and speed, respectively, as a standard in the US and the rest of world excluding a few regions which chose the metric system? And, when was this standard put into effect, considering that the American aircraft in game all use miles per hour for indicating speed?

Thanks in advanced.

It was a carry over from Naval terms, as some of the earliest aircraft were Naval types and an Aircraft was seen as an extension of the fleet....

A knot incidentally was the way you used to measure the fwd speed of a ship, a lump of wood with a rope attached to it was thrown over the back end of the boat and as you sailed away, the rope with knots in it was fed out........ you counted the knots over a time to give you your fwd speed http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

Friendly_flyer
08-11-2007, 08:26 AM
These days the knots/feet is the standard, but I guess that in 50 years or so, the metric system will apply to aeroplanes as well. Being raised with the metric system, I only use knots (or mph)/feet since the squadron communicate in it, and I can't be bothered to calculate back and forth every time I need to state my altitude.

Skoshi Tiger
08-11-2007, 09:06 AM
Just from an international perspective, In places like Australia that use a metric system, only Alitude is measured in 'Feet'. All horizontal distances are measured in metres and kilometres. (Except when your navigating and you and use the units displayed on your ASI so you don't have to convert between units of mesurement!)

This stems from the fact that altitude is measured using an altimeter. The reading on this instrument depends on a setting that is set by pilot. If two pilots have different setting then the altitude being displayed will be diferent in the two aircraft, a potentially dangerous circumstance.

Now, Australia like all other reasonable contries abide by a set of international regulations that state that if you are flying at a low altitude (below 10000 feet) you set your altimeter to the Area QNH. This is a forcast value and is valid for about 3 hours from the time it is forcast. So if all pilots use the same forcast then everything is peachy!

If your flying at a high level ( when you get above above 10000 feet) you set your altimeter to 1013.2 which is the the sea level pressure in the standard atmosphere.

So the planes using the two settings don't bump into one another there is a transitional level that you don't fly in (except for asending or desending) that goes from 10000 feet to Flight Level 110. ( They even change the way you report your altitude!)

Now using both systems the actual chance of the altitude thats being displayed on your altimeter and your actual height (in Feet, metres or cubits ) above sea level being the same is quite small. So small in fact that the French, who own the copyright on the Metre, won't let anyone use the term unless the Altitude displayed actually corresponds to height in metres!

Even using Radar Altimetres you would only find your height above ground and not you altitude above sealevel. So you'ld need a GPS and a very detailed map of the terain to work out your altitude.

So it will be a while till aircraft start using heights in metres!

BrotherVoodoo
08-11-2007, 03:25 PM
I guess they did not use knotts in WWII or is this speedbar option missing from the game?

berg417448
08-11-2007, 03:38 PM
USN aviators used knots in WWII. I'm pretty sure that the Royal Navy and the Japanese Navy aviators used knots too.

You can toggle the speed bar in game to show knots if you wish.

Friendly_flyer
08-11-2007, 03:48 PM
The speedometer on the Hurricane is in knots.

Daiichidoku
08-11-2007, 03:57 PM
Are you suggesting that coconuts migrate?


http://img.photobucket.com/albums/v479/Daiichidoku/HolyGrail001.jpg

BrotherVoodoo
08-11-2007, 05:04 PM
Knots is the KIAS speedbar option then? Knotts Idicated Airspeed?

Skoshi Tiger
08-11-2007, 11:01 PM
Are you suggesting that coconuts migrate?



Only when attached to the appropriately sized migratory swallow.

Ozzie built CAC-23 Mustangs had their ASI in Knots but our imported US built Mustangs had theirs in miles. That would keep the pilots on theur toes!

Friendly_flyer
08-12-2007, 08:25 AM
Originally posted by BrotherVoodoo:
Knots is the KIAS speedbar option then? Knotts Idicated Airspeed?

It should be, according to Wikipedia:

KIAS is "knots indicated airspeed", meaning the airspeed shown on the airspeed indicator

stansdds
08-13-2007, 04:09 AM
Originally posted by BrotherVoodoo:
Knots is the KIAS speedbar option then? Knotts Idicated Airspeed?

Yes. Knots Indicated Air Speed. That is what is displayed by the cockpit airspeed indicator, but that is not usually your true airspeed (TAS) except at sea level.

Skunk_438RCAF
08-13-2007, 07:24 AM
Originally posted by berg417448:
the Japanese Navy aviators used knots too.


Isnt the Zero's ASI in Kilometers?

berg417448
08-13-2007, 09:11 AM
Originally posted by Skunk_438RCAF:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by berg417448:
the Japanese Navy aviators used knots too.


Isnt the Zero's ASI in Kilometers? </div></BLOCKQUOTE>

Just checked the A6M2. It displays knots.

Sergio_101
08-13-2007, 09:21 AM
Feet and knots,

Knots is a carry over from using nautical/maritime
charts for navagation.

Feet is more of a carry over from the British and American
surveys of mountians of the world.
Mountains can ruin your day as you convert feet into Meters.

Most US aircraft had airspeed indicators calibrated in MPH, not Knots.

Sergio

DuxCorvan
08-13-2007, 05:19 PM
F*ng liberals, I only use our royal traditional local measure system in Fartsmells, Cricketleaps and Leperfingers. http://forums.ubi.com/images/smilies/16x16_smiley-mad.gif