Can you clarify a few things regarding Vspeeds for me.
Vne usually is used in light aircraft like this. You stay in the green and if you fly too fast into the yellow you slow down, back into the green. Your manual for the aircraft, give you the speeds and other information.
Past Vne, you can have structural damage.
Here was some discussion about Vspeeds, and some pilots/people have different opinions. With research we can find the definitions and meanings.
http://forum.canardaviation.com/showthread.php?t=334
Wiki covers definitions and discusses Vspeeds.
http://en.wikipedia.org/wiki/V_speeds
The Vspeeds for 767-200 are in a FAA certification document, A1NM.
http://rgl.faa.gov/Regulatory_and_G...1DC94F8EA7EDC09986257674007756F7?OpenDocument
How is VMO different from VNE
Vmo - maximum operating limit speed
Vne - never-exceed speed
I used Vne in light aircraft and Vmo in large jets.
VNE - never exceed speed. The speed which must not be exceeded in a glide or dive or other maneuvers in smooth air. The red line at the top end of the ASI yellow arc, usually 90% of the 'design diving speed' - VD - which latter is usually 1.4 times VNO.
VNO - maximum structural cruise speed. The top end of the ASI green arc. When cruising at, and below, VNO the aircraft should not be damaged by a 35-knot vertical gust; which is at the bottom end of the severe turbulence scale.
Flight above VNO should only be conducted cautiously and in smooth air.
From the European Aviation Safety Agency...
CS 25.1505 Maximum operating limit speed
The maximum operating limit speed (VMO/MMO, airspeed or Mach number, whichever is critical at a particular altitude) is a speed that may not be
deliberately exceeded in any regime of flight (climb, cruise, or descent), unless a higher speed is authorized for flight test or pilot training
operations. VMO/MMO must be established so that it is not greater than the design cruising speed VC and so that it is sufficiently below VD/MD or
VDF/MDF,to make it highly improbable that the latter speeds will be inadvertently exceeded in operations. The speed margin between VMO/MMO and VD/MD or VDF/MDF may not be less than that determined under CS 25.335(b) or found necessary during the flight tests conducted under CS 25.253.
Since the terrorists don't care about rules, they exceeded Vmo because they can.
Proved on 911, a 767-222 can exceed Vmo to 515 knots and crash into the WTC.
When I exceeded Vmo on a flyby in a KC-135 at 500 feet, nothing happened, but as soon as I realized I had accelerated from 300 KIAS to over 370 KIAS I moved the throttles to Idle and coasted to a pull up to downwind. Why was I over 250 KIAS below 10,000? I was in formation with T-38s and a SR-71 and they have a waiver to fly 300 KIAS or as needed by their performance for safety, and we were in loose formation behind them.
Vmo in the KC-135 was 350 KCAS, it varies with altitude and is about 370 KIAS at 27,000 feet I believe. The MACH limit, .9 MACH for the KC-135 came into play at higher altitudes. Some where in our manual and performance data was the fact the KC-135 was test flown to .95 MACH.
The 767-200...
Airspeed Limits: VD = 420 KCAS to 17,854 ft/.91M above 23,000 ft, linear variation between these points.
VFC = 390 KCAS to 17,600 ft/382 KCAS at 23,000 ft/.87M above 26,000 ft, linear variation between these points.
VMO = 360 KCAS/.86M
Whats all this about a dive speed.... how does this work?
Vd - design diving speed
911 truth conspiracy theorists would like to say 11 was over Vmo, but Vd in the 767 cert, of 420 knots. Flt 11 was going about Vd at impact.
And also at low speeds wouldn't the speeds be referenced to KIAS to KTAS rather than mach numbers.. I would have thought the air too thick to reach those speeds without structural failure.
For the 767, VMO = 360 KCAS/.86M, KCAS is close to KIAS and KTAS at low
altitude, sort of.
What speed does a 767 break up? We know 175 was going 510 knots! Did not see nay parts falling off. From flight test done on 911, a 767-222 can reach speeds of 510 knots at low altitude and appears to be flying with no visible structural failure. NICE to know when you fly a Boeing it was designed
not to break up 150 knots over Vmo at 700 feet.
What does Boeing say about flight over 360 KCAS in a 767? What can Boeing legally say and not be sued when an idiot pilot decides to exceed Vmo and breaks the plane due to negligence because Boeing said they can go 580 knots; Boeing can't say that????
Boeing says! (for Mr Deets), or what Boeing can say.
Exceeding Vmo/Mmo can pose a threat to exceeding design structural integrity and design stability & control criteria of the airplane. At speeds less than Vmo/Mmo the airplane’s flight characteristics have been confirmed by flight testing to meet FAR requirements. At speeds in excess of Vmo/Mmo, however, normal airplane handling characteristics are not assured.
http://www.biggles-software.com/software/757_tech/flight_instruments/_popup_for_40_vmo_mmo.htm
^ Boeing says exceeding Vmo can pose a threat. Deets, forgot to check with Boeing to see what they say; what they can say, "can pose a threat".
^^ Boeing says, normal airplane handling characteristics are not assured above Vmo.
Boeing did not say at 150 knots over Vmo the plane falls apart. Boeing said when you exceed Vmo, there is a possibility of a threat to structural integrity, and handling characteristics are not assured.
Mr Deets never said much of anything, he implies Flight 175
can NOT fly 510 knots and hit the WTC. He is wrong and unable to present evidence to support his non-point.