# Tag Info

61

When you are breathing, oxygen ($\mathrm{O}_2$) and carbon dioxide ($\mathrm{CO}_2$) are exchanged between the alveoli in your lungs and the environment. This gas exchange is based on diffusion, which means the partial pressures of each gas involved will move towards equalization: Henry’s law states that the amount of a specific gas that dissolves in a ...

61

I'm a controller, not a pilot, so I can only speak from my own perspective. What we are taught in ATC school is that many pilots are reluctant to use the word mayday because they feel it might escalate a situation unnecessarily and potentially create a lot of paperwork. I guess, mentally, it seems like calling mayday is a significant, irreversible step which ...

42

To supplement Jimmy's answer, if they had to land right away, they could have; it just would've resulted in an overweight landing being recorded, and which on most airliners triggers a special inspection of the landing gear and its attaching structure, and if nothing is permanently bent or cracked or broken, you are good to go. An overweight landing in ...

26

Saying mayday or pan-pan is only recommended, and repeating it three times is merely preferable. That statement applies to USA, and ICAO in general, by referencing both the AIM and AIP; and ICAO's Annex 10 Volume 2, respectively. Let's begin with the basic (from the linked AIP): A pilot who encounters a distress or urgency condition can obtain ...

24

The situation in a high altitude depressurization is different because: The air in your lungs is now "FL500 air" - i.e. the pressure is about 0.1 atmosphere. This means that the partial pressure of O2 (ppO2) is about 0.021 atm, instead of 0.21 atm. Oxygen will rapidly diffuse out of your blood and into your lungs, and your brain will very soon not have ...

24

I think the characterization that it's "too heavy to land safely" is erroneous; the fuel burning is probably out of circumspection and to allow for a better safety margin. The runway length may also be beyond the landing field length and/or the brake energy limit of the heavy weight, so decreasing weight would add to the safety if immediate return to land is ...

22

It isn't practical for a number of reasons: Intentional stalls are inherently dangerous. Stall-spin accidents are a major cause of accidents, stall recognition and recovery are taught specifically to avoid stalls. Some airplanes have docile stall characteristics, but even those can still bite you. A Cessna 172 will drop a wing is mishandled, especially ...

20

An interceptor can gain cooperation from an intercepted aircraft by means of a show of force ie forming up on the target’s 6 and 9 o clock position and attempting to contact them on the emergency radio channel. If the target remains unresponsive or refuses to comply, a fighter will often cut in front of its flight path in afterburner, causing the target ...

14

The hook is for emergency use at airports that have Runway Arrestor Systems. Lots of non-naval fighters have arrestor hooks for that purpose. Now, there is nothing stopping someone from landing an F-16 or any other fighter on a carrier deck and using its arrestor system, which works the same way. The main issues are the proficiency required to do it and ...

13

Normally, a stall and controlled flight are mutually exclusive. That AF447 would descend as it did has to do with the relaxed static stability of the A330 and its rear cg location as well as the docile behavior of its airfoils with large separation on the upper side. In short: With some aircraft this is indeed possible and practical but with others it is ...

12

Flaps steepen the descent angle - in other words, you run the risk of falling short of the runway. So in a glide you keep the flaps up until you can be certain of making the landing point. Once the landing is guaranteed, you can then deploy gear as well as flap to slow down as much as possible - being aware that these actions will further reduce the gliding ...

11

You don’t need a new technique You don’t normally stall jetliners. And in a crisis the last thing you want to do is learn a new technique. Besides, they already have a trained practice for descending jetliners very quickly. It’s used for loss of cabin pressure. While the procedure normally levels at 10,000’/3000m, it could certainly be extended. Anyway, ...

10

The jet fighters could harass the small plane, to the point of making it very clear: You will not get much farther on this path! Note what happens when the F-14s fly under the Zeroes here: The Zeroes aren't waggling their wings. This is an upset - they are being flipped over by the wake vortex from the Tomcats. The ...

10

It is smarter to roll onto your side and maintain unstalled flight, executing a emergency spiral descent. G loads on the wings are much lower as there is no need to maintain altitude, only to control airspeed. With all due respect to our beloved Langewiesche, "mushing glide" technique is for much lower wing loaded gliders that are easily unstalled ...

9

The simple answer is no, there are no "subclassifications" of emergency or urgency calls in standard aviation phraseology. In terms of priority, they are all the same; however, in terms of actions taken, there can be differences based on what caused the aircraft in question to make the emergency or urgency call. There's mayday (emergency), pan-pan (urgency),...

9

Yes the F-16 would be able to land on a carrier however it would most likely break/damage the landing gear and other components because it's not built for it. I am only assuming this, but I believe the net as shown in the picture could catch several non-naval aircraft including a F-16.

9

It is the advice of the FAA that you should be looking out the window quite a bit when VFR in the pattern. According to this AC related to traffic patterns: Collision Avoidance. The pilot in command’s (PIC) primary responsibility is to see and avoid other aircraft and to help them see and avoid his or her aircraft. Keep lights and strobes on. The use ...

9

For one you can not "land on water" you can ditch an aircraft in a body of water but you would be hard pressed to call it a landing. You can however, "land in a grass field" or "land on a runway nearby" or "land on a highway" all of which are substantially more controllable then trying to stall a few feet above the ocean. The result of catching an edge ...

8

If you are confused somehow about your situation over an airport, and there are other aircraft around, head for empty sky away from the airport beyond the pattern/circuit and get reoriented. By empty sky, I mean if you think somebody might be nearby and you aren't sure where they are and don't have them in sight, identify a patch of sky where they're not, ...

8

It's explained in the final report. Most definitely they asked him what he meant, as the transcript itself is: * * switch? "*" denoting unintelligible words by the transcribers. The first officer was referring to the cabin emergency notification switch, which provides a signal to the cabin crew members indicating that an emergency has occurred. To ...

7

No, the F-16 cannot "carrier land", even with the tail hook. The Air Force jets (aside from any that are shared with the Navy) have tail hooks only for emergency purposes during landing, or securing the aircraft during engine run-up testing. The tail hooks are not designed to arrest an aircraft like it would for a carrier landing, the land-based arresting ...

7

Let's assume you started exactly with ICAO minimum fuel required (as explained in What are the ICAO fuel reserve requirements?): Taxi fuel Let's assume you used all of it at your departure airport. Trip fuel Used for the flight to the destination airport. Contingency fuel Let's assume this was used in a holding pattern at the destination. Alternate fuel ...

7

"Mayday, Mayday, Mayday" tells ATC (and everyone else on frequency) that you have an emergency, but it gives them exactly zero information about the nature of the emergency or what you need other than getting their attention and time on frequency. If you're in a portion of flight where you don't already have the attention of the controller, then adding "...

6

The F-111 capsule was great and I always felt glad to have it, especially at high speed. However in my 8 years flying in it, I'm not sure that the ejections I knew about were much different statistically. The fatal outcomes were late, upside down in a rapid roll or otherwise outside the parameters and the successful ones were mostly okay with a few non-...

6

I flew to Libya under humanitarian support in 2013 when there was a civil war going. We flew with the technician to operate cargo doors and one cabin crew to support us. We were carrying a cargo of medicine and food with Airbus A320. It may not be the complete answer of yours but we followed a special procedure as; Malta control was the closest and working ...

6

In the U.S. at least, HADR doesn't launch aircraft until a crisis aka disaster has been identified, even if at launch they don't yet know if the problem is lack of potable water or civil unrest over rigged elections. An already flying commercial airliner won't have a glut of doctors and medicine unless it's been chartered for an already identified crisis, ...

6

That would be up to the discretion of the flight crew, what forced landing site they selected, approach route, etc. Typically deployment of flaps in a forced landing scenario will only be done once the airplane is guaranteed to make the landing site by gliding in that landing configuration.

6

No nothing like that. If there was what is usually called "explosive" decompression, like a window blowing out, there will be a loud BANG, maybe a short howling sound as air rushes out, possibly fog will form in the cabin, and you will feel the air pressure in your head trying to get out until it equalizes. It might make your ear drums hurt until it does. ...

6

Whether or not an airlines is in an emergency situation is not a black or white question. There are millions of different internal and external factors that come into play, any combination of which may or may not be considered an emergency. No computer can be programmed to accurately and consistently calculate whether or not a flight is having an emergency ...

5

No. An abnormal/emergency situation is a situation that applies to a single aircraft at a specific time. COVID-19 does not (generally) pose a specific risk to a specific aircraft. Obviously the entire aviation industry is in very bad shape at the moment, but that is not what we mean when we talk about an "emergency" in aviation.

Only top voted, non community-wiki answers of a minimum length are eligible