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39

"Speed" is not a singular term in aviation. There are many different ways to measure speed. See for example Why is there a difference between GPS Speed and Indicator speed? Most commercial jets cruise with a true airspeed in the range 400-500 knots and an indicated airspeed in the range 200-300 knots. For the purpose of passenger transportation, ground ...


37

Faster aircraft often overtake slower on the same routing. This is usually accomplished by flying at higher or lower altitudes. This is called vertical separation. They can also be separated laterally by radar vectors so that they are 3-5 nautical miles apart. The exact distance will depend on the ATC standards for the particular airspace. Often as they ...


27

Other than the TU-144 and Concorde, the record for the fastest True Airspeed in an airliner probably belongs to a DC-8. Wikipedia Douglas DC-8 On August 21, 1961, a Douglas DC-8 broke the sound barrier at Mach 1.012 (660 mph/1,062 km/h) while in a controlled dive through 41,000 feet (12,497 m) and maintained that speed for 16 seconds. The flight was to ...


25

The de Havilland Comet quickly comes to mind, with the airplane grounded after two catastrophic break ups in flight. The Comet was returned to service once the problem had been identified and corrected in 1958. Too late, however for the airplane to be a commercial success as the Boeing 707 had captured most of the commercial jet market in the intervening ...


23

Your scenario isn't really realistic, the turn coordinator and the AI are almost always on different sources of power to protect against this very event. The TC is almost always electrically driven because it gives an alternate source of information. A loss of an instrument or even a whole suite of instruments is something instrument rated pilots train for,...


20

I think I know what you're asking, and the Concorde-excluded answer is almost certianly the Convair 990 which could get just shy of Mach 1. From wikipedia: The Convair 990A is still the fastest non-supersonic commercial transport to have ever been produced. During May 1961, one of the pre-production 990 prototype aircraft set a record of .97 Mach in ...


16

GdD’s answer is accurate (up vote). My answer will be more step by step. The first thing you should do is recognize the issue. That might not be immediately easy depending on your aircraft and it’s electronics suite. If there is no visual and auditory alert, you will have to wait for the gyros to wind down to a certain extent. Immediately announce to ...


15

In the United States, no, the airline does not pay the NTSB or the FAA for accident investigations. This is considered a public service and is paid for by tax funds. That doesn't necessarily mean that they won't pay for anything. For example if the NTSB has to remove wreckage to examine it, they will often have the insurance company pay for the removal and ...


15

Most (all?) modern airliners are, in fact, certified to land at any weight up to MTOW if necessary, but if they do land at more than MLW then a special "Overweight/Heavy Landing Inspection" must be performed before the aircraft can be used again. As this Boeing document states: Overweight landings are safe because of the conservatism required in the ...


15

Who else might make that call? The airline? Yes, if the airline thinks the weather is too bad at a particular airport for safe operations, it can just cancel all flights from that airport without asking the pilots. The airport? If the airport closes completely, then it is closed. No flights can depart any more, even if the pilots consider it safe. Is ...


7

If the fastest crossing of the Atlantic is your metric, the winner is the Vickers VC-10. It was very advanced for its time with airfoils close to what today would be called supercritical. In 1979, Super VC-10 G-ASGC took off from JFK to land just five hours and one minute later at Prestwick. The scheduled time was six hours and twenty minutes. This record ...


6

Is it possible to use refrigeration technology to cool down the aircraft's skin so it can reach much higher speeds? Fundamentally: no. Refrigeration technology moves heat energy around, it doesn't get rid of it. Your fridge moves heat from inside to the outside. To get rid of it, you have two means, broadly speaking: Heat up some mass and throw it away ...


5

I guess it depends on what you consider to be a "high level of integrity and safety." VOR is a perfectly acceptable means of navigation if you know how to use it. And, I guess, if the transmitter hasn't been flooded. Let's take a look at the data for the Las Vegas VOR: Now, that does look like a lot of "unusable" radials, but it's not actually as bad as ...


5

Most of the fastest airliners are limited by the speed of sound, and their speeds (actually Mach numbers) are within a narrow range so the values are quite similar. This is because the aerodynamics of a transonic airplane will create various instabilities and stalls near the sound speed limit where the local flow at the wing is already locally supersonic. ...


5

The 172S POH, the current version in production indicates: FUEL VENTING Fuel system venting is essential to system operation. Blockage of the system will result in decreasing fuel flow and eventual engine stoppage. Venting is accomplished by an interconnecting line from the right fuel tank to the left tank. The left fuel tank is vented overboard through a ...


5

The OEM will have its own Product Safety organization, staffed with investigators and analysts, that participates and supports accident investigations with its own internal contingency budget. So when a crash happens, a team is formed with the Regulator (FAA), the Gov't Investigator (NSTB), investigators or representatives from the OEM, and investigators or ...


4

Boeing's officially stated reason in the report is: ... to prevent pilots from inadvertently activating TO/GA mode at or after touchdown. Inadvertent activation of TO/GA could result, among other things, in the aircraft departing[1] the runway. ... [1] As in runway overrun/excursion. Which is in accordance with AC120-29A (also from the report), where: ...


4

The SR-71 speed was limited by the maximum allowable temperature of the air entering the first stage compressor at the front of the engine (~800F). The airframe heat load at mach 3 would far exceed the heat transfer capacity of any refrigeration system that could possibly fit inside the plane, and its weight would reduce its useful payload to zero. A better ...


3

At the end of the day, the final authority on making, or not making the flight has to rest with the pilot. If you reverse the question, and a pilot thought that it wasn't safe to go, but there was an outside force saying they had to go, that wouldn't be ideal either. Since you didn't mention specifics, there isn't a way to dig into other specifics, but ...


3

It is common. In fact, for aircraft parked at a gate (i.e. not a hardstand), it is quite uncommon NOT to start the first engine during pushback. The wing-walkers stay well away from the intakes, and with the engines at idle power, the danger zone isn't all that large - not nearly as large as if the motor were running at a high power setting.


2

First of all, if there are two commercial airplane flying towards same destination, in same flight path there will 2000 feet difference in altitude and can be overtaken if the 2nd aircraft got greater tailwind than 1st aircraft. Hope it’s clarify.


2

And this just in: In Peter Kämpf's answer he presented Atlantic crossing as one of the metrics, and the age-old Vickers VC-10 record has been beated. The new subsonic atlantic crossing record (this time New York JFK to London LHR) stands at 4 hours and 56 minutes. A staggering 80 minute gain enroute! BBC: Storm Ciara helps plane beat transatlantic flight ...


2

Buy one of the devices that gives you GPS plus AHARS, and make sure that it’s calibrated with ForeFlight and your iPad on EVERY FLIGHT. THen in the bizarre situation that your vacuum AND electric fail simultaneously you can STILL land using just your iPad. Oh... and for sure check this by flying an approach with an instructor and failing ALL instruments to ...


2

It is a very good question, in light of what happened with the Lion Air flight 610 crash. Caused by a single mis-calibrated AoA sensor, resulting in 189 deaths. Single inputs into flight automation are allowed, if the single input can be safely disregarded by the on-board systems. A safety analysis will take into account: what the consequences of the ...


2

You can buy aircraft life vests pretty inexpensively for the purpose of having one or seeing how they work. There are a bunch of used ones for sale on eBay, they may have been taken from planes over the years or they may just find their way into circulation after being removed (before being trashed). Some of them get upcycled/recycled into other things ...


2

The only time it would make sense as a normal or abnormal procedure to turn off altitude reporting is when your static encoder system is reporting no or incorrect altitude information. Especially in today’s world of mandatory Mode C and/or ADS-b in certain airspaces. ATC in those airspaces may have you cycle your system temporarily. Or, they could have you ...


1

Some modern landing lights have a pulsating or alternating mode. It's just for being recognized more easily, has nothing to do with an emergency. A constant white light heading right for you over a city full of lights doesn't get as much attention as a pulsating light which gets bigger each time as you get closer :)


1

NEodd, SWeven, North to East “odd” altitude plus 500. SWeven, South to West “even” altitude plus 500. East is least and West is best is for magnetic variation when figuring true course ves magnetic course.


1

The question is pretty old. This post is to add new info. Since this question is about hiking, a PLB like one from manufacturers ACR or by Ocean signal would work well. And, they are personal sized. I believe they are both 121.5 and 406 dual transmitting. The manufacturers include instructions and paperwork for registering them with SARSAT making them legal ...


1

We didn’t have a static hook in my day. I will tell you, sometimes the pilots would relieve the static charge by grounding the aircraft themselves. Sometimes, they did not. The static charge would vary From moderate to severe. And, it could even be felt by your partner who was bracing you by the legs. After the first couple of volunteer troopers started ...


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