10/23 Raptor Video

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Marc Zeitlin

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different time on the UK flight aware (EDT). I don't know why the different rate.
Because the 686 is in fpm, and the 209 is in meters/minute. The ratio is exactly feet to meters. So this silly argument about descent rates and speeds does, in fact, show 188 mph / 163 kts GS at a descent rate of 686 fpm / 209 mpm.

In my relatively low drag canard COZY MKIV, I can easily pick up 20 kts - 30 kts by pointing the nose down and descending at 700 fpm. Not that whatever speed PM may have achieved, in a descent or not, means anything whatsoever here with respect to the original performance claims, or otherwise.
 

BBerson

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Right.:) It just says Rate (who ever heard of mpm) :mad:
In any case, he exceeded 150 kts (153) the next day while climbing. It doesn't mean anything with respect to obvious crazy performance estimates (claims?) but it does prove it didn't flutter at that speed and flew almost 3 hours.
 

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Malish

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(who ever heard of mpm)
You're right!
In metric system air speed always measured in Meters Per Second(MPS) or in Kilometers Per Hour(KPH).
Aircraft vertical speed - always in MPS
Aircraft air speed - in KPH, but sometimes can be in MPS.
Wind speed - always in MPS.
MPS multiplied by 3,6 will be KPH(10mps X 3,6 = 36kph).
 
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BBerson

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You're right!
In metric system air speed always measured in Meters Per Second(MPS) or in Kilometers Per Hour(KPH).
Aircraft vertical speed - always in MPS
Aircraft air speed - in KPH, but sometimes can be in MPS.
Wind speed - always in MPS.
MPS multiplied by 3,6 will be KPH(10mps X 3,6 = 36kph).
But what is the international system for aviation?
I thought it was knots for airspeed and wind, feet for altitude, and fpm for vertical rate.
 

BBerson

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obvious crazy performance estimates (claims?)
The website listed estimates. The word claims is to say as true or fact with no evidence.
It's impossible to say what the true performance or weight is before proven. Burt Rutan doesn't give performance before testing, but that's his choice. Industry standard is more about unproven questimates, it seems.
This prototype has proven the weight estimate was incorrect but could be changed with a different engine. Performance measurements are not done yet but is improving gradually. If the cooling is only half needed as some claim then he is flying at half power and could be improved.
It was reported here that one deposit holder said he would be happy with 75% of the stated performance estimates.
And that could be the goal.
 

Hephaestus

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But what is the international system for aviation?
I thought it was knots for airspeed and wind, feet for altitude, and fpm for vertical rate.
No, pretty much the rest of the world is metric. EASA works in kmh and meters...

Some day you guys should learn to convert ;)
 

Vigilant1

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Some day you guys should learn to convert ;)
I know you"re just ribbing us, but part of the problem, (IMO), is that we were taught to convert. Converting isn't hard, but if you don't make the jump to thinking and working in the metric units, it never ”takes."
 
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PredragVasic

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ICAO wants SI units. But what is actually used is listed here: International Civil Aviation Organization - Wikipedia
So, for those who can't be bothered to read the links, SI system of measurements (metric) is the standard system for units of measurement to be used in the international civil aviation. There is a temporary permission that allows use of non-standard, non-metric units (nautical miles, feet).

Most airplanes and gliders manufactured in EU (and destined for the EU market) have airspeed indicators in kmh, altitude in m and vertical speed in m/sec. Most of the domestic aviation information is reported in metric (wind speed in m/sec, runway lengths in m, visibility/ceiling in m).

The ICAO has not set an expiration date on that temporary permission for non-standard units, though. Perhaps they are waiting for the one country that uses them to convert to metric...
 

Rataplan

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I know you"re just ribbing us, but part of the problem, (IMO), is that we were taught to convert. Converting isn't hard, but if you don't make the jump to thinking and working in the metric units, it never ”takes."
Metric in anyway very logic and imaginable. I mean if I talk about 1 liter you know its 10x10x10 cm and if you fill it with water its also 1 kg. also Kilometer means 1000 meter, centimeter means a hundred of a meter . the earth is divided in 400 degrees each degree in 100 'minutes' , each 'minute' is a km like each minute of 360 deg is a nM . Flying a plane with Km/h m/s or one with kts fpm never bothered me... What I don't like is flying same type of plane but airspeed in Mph . thats confusing
 

Vigilant1

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Metric in anyway very logic and imaginable. I mean if I talk about 1 liter you know its 10x10x10 cm and if you fill it with water its also 1 kg. also Kilometer means 1000 meter, centimeter means a hundred of a meter.
I agree SI has a lot going for it. But the American public never got to see any advantages because they were just converting and still doing the work in their "native tongue", then converting back to SI. It wasn't better or easier, it was worse. To switch over, you need to just switch over.
One >minor < advantage of Imperial: it forces users to pay attention to units when using fomulii. This can serve as a double check as you manipulate equations. When using metric units, because most things are in base 10, a person may be tempted to just do the manipulations and affix the appropriate unit to the final result.
 
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Malish

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I would say that metric system is mush easy to work with, but I can fly in both systems - it's easy to convert them:
1mph = 1.6 kph
1knot = 1.8 kph
1000 feet = about 300 meters(1/3)
And if you can remember - 1 foot = about 0.3 meters and minute have 60 seconds, then you can figure your vertical/or wind speed too ;)
 

Hephaestus

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I know you"re just ribbing us, but part of the problem, (IMO), is that we were taught to convert. Converting isn't hard, but if you don't make the jump to thinking and working in the metric units, it never ”takes."
It's really not hard - at work where we use "silly metric" and imperial interchangeably it gets amusing at times... (silly metric - my term, for whatever reason our metric construction drawings - are all set in millimeters, so that 10 mile run of pipe is listed as 16093440mm rather than anything approaching logical units)

Just don't talk about good ol 2x4's in a metric vs imperial discussion - it gets ugly :)
 
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