45

They're different usage cases, and have to be engineered differently. Three major points: A shark tag doesn't have to survive a 500mph impact (#7 on the list) with the ground, and a flight recorder has to be able to do so. It adds a lot of padding and weight, and limits the kind of battery that can be used. Sharks also don't dive to a depth much greater ...


43

how they can come up with such specific paths? Diagrams in news organisations graphics published in March and April 2014 vary widely in what they show and appear to be artistic impressions. These should not be relied on in any way. To calculate a variety of likely flight paths, it seems Inmarsat engineers, and other parties to the official investigation, ...


20

The "related article" specified in your link has this to say: Searching one possible flight path, Australia said it would focus its efforts in a specific stretch of the southern Indian Ocean, using computer models of the plane’s possible flight path that take into account undisclosed satellite data, wind conditions and ocean currents and some ...


20

I would treat an active SOS signal from the ground the same way I would treat an ELT signal on 121.5: Contact ATC (or Flight Service if you're not sure what ATC frequency to use) and inform them of the event. As with reporting an ELT you should be prepared to tell ATC: What kind of signal you've observed (ELT, signal light, signal mirror, "SOS" or "HELP" ...


17

There are four different types of ELTs: Automatic fixed ELT (ELT(AF)). An automatically activated ELT which is permanently attached to an aircraft. Automatic portable ELT (ELT(AP)). An automatically activated ELT which is rigidly attached to an aircraft but readily removable from the aircraft. Automatic deployable ELT (ELT(AD)). An ELT which is rigidly ...


17

The CVR and FDR have impact switches to stop recording when they experience high acceleration. In incidents and accidents that don't involve high enough acceleration, the plane remains intact enough for the boxes to be immediately found and switched off manually. In more serious crashes, the boxes stop recording because of the physical destruction of ...


14

This excellent explanation is taken from Avionics News in 2006: FDRs are equipped with an Underwater Locator Beacon (ULB). If you look at a picture of an FDR, you will almost always see a small, cylindrical object attached to one end of the device. If a plane crashes into the water, this beacon sends out an ultrasonic pulse that cannot be heard by human ...


14

There are almost always opportunities to volunteer. However, joining CAP is a larger commitment than simply saying "I'd like to volunteer to fly." You will need to attend regular meetings and perform non-pilot duties such has becoming an administrative officer or participating in recruiting and fund raising activities. For some squadrons, the budgets are ...


13

Bluefin-21 Why not multiple Bluefin-21's There is only one Bluefin-21. The other Bluefins 12S, 12D, 9M etc are mostly for shallow water work. Other AUVs The Bluefin-21 is not the only commercial Autonomous Underwater Vehicle (AUV) equipped with side-scan sonar. The US Navy has spent $20M on an order for eight Knifefish (a Bluefin-21 derivative) but ...


12

Shark tags work by only sending the logged data when the shark resurfaces. Between those it just stores the data in memory until it can send it. Sending underwater takes a lot of power otherwise.


11

Yes, but only under highly unlikely circumstances. An airplane contains all sorts of materials that float, from fuel to seat cushions to the plastic cups in the galley. In order to sink without leaving any floating wreckage, all of that material would need to be trapped within the airplane while it fills with water. In order for this to happen, the ...


9

In the United States, CVRs and FDRs have a 10 minute (+/- 1 minute) battery requirement to allow any available post-crash voice and data to be recorded, with power removed once a timer limit is reached. While I'm not familiar with the internals of the FDR, simple circuitry could trigger the timer to start based on current flow from the battery, if not for ...


8

My personal guess: I think what they've done is to start a line where from where the plane was last known, and then intersected it with the arc where the distance would have been correct at cruise speed with reference to the time. Example with just some values. Since the arc radius and time was known, one would be able to draw a line which would show ...


8

Would better location tracking for airliners improve safety? Very simply, no.... us knowing where AF447 was would have made exactly zero difference to the fact that it crashed into the ocean at 400+ knots. Would we have had a better idea of where to find it? Most probably. Would it have saved any lives? Absolutely not. As always, these things come down to ...


8

What is the terrain/glacier situation [on the southeast side of Mt Redoubt]? The southeast side is all glacier, forming in the valleys formed by previous formative eruptions, which have deepened significantly due to glacier flow. These glaciers do move and churn, so unless the plane crashed on top of one of the prominent ridges then the position of the ...


6

FWIW, I was specifically taught to use "pan-pan" for a scenario like that, at least to get the controllers' attention; anything more depends on the specific situation. My instructor said that pan-pan is always a good way to relay distress calls or other urgent conditions that don't affect your aircraft directly. I've never seen any formal document to ...


6

Straight Down is most likely the best angle but there is of course cases to be made for other scenarios. In your case if you are looking for something on the ground that is potentially obstructed a straight down view is going to give you the most direct view and will prevent something from falling out of frame if an angled view cause an obstruction to block ...


6

I spent an enormous amount of my childhood & early teens looking out the window of my father's Cessna 337. I found that to look as close to vertically down as possible is actually quite unnatural, the eye will unconsciously keep fixating on details & then whip-panning to the next random detail. The fovea (the surprisingly small area of decent vision ...


5

Search and Rescue is under the ICAO umbrella, but also with the IMO. Annex 12 to the Convention on International Civil Aviation gives the international standards and recommended practices (SARPS) on Search and Rescue. The annex is supplemented by the International Aeronautical and Maritime Search and Rescue (IAMSAR) Manual, which is published by the ...


5

Another consideration is to look at other aviation sources that perform search and rescue. Civil Air Patrol (CAP) for example, use aircraft routinely to search for aircraft. A quick read through their Mission Aircrew Reference Text Volume III: Airborne Photographer manual has this to say about the advantages and disadvantages of high and low oblique angles ...


5

Civil For the UK as requested, this information is in § 2.32 of the Radiotelephony Manual (CAP 413). The call-sign for a Helicopter Emergency Medical Service (HEMS) is three parts: HELIMED Two-digit identifier unique to the aircraft (list on Wikipedia). Suffix A or E A for a helicopter en-route to an emergency or to a hospital with patient(s) on board E ...


5

The picture says that "If [the above facts are] true, the plane can only be at one of two green dot locations." However, it doesn't give any reasoning or evidence to support this claim. So, there's no reason to think that the claim is correct. You asked if itʼs possible to prove that the method is wrong. Itʼs not possible to prove that the method is wrong, ...


4

In crash the last two hours before the crash is most important, so the recorder always recording and stopping when the plane crashes either because of crash sensor or simply due to loss of power and input as the wires leading to it are torn by the impact forces is the right thing. However in some incidents¹ the data would also be useful. When the crew ...


4

who operates the hoist in the Coast Guard helicopter SAR teams? This depends on country and other factors, perhaps aircraft type etc. In general, the winchman descends on the end of the winch cable and does not operate the winch. In the UK, helicopter search and rescue were, until recently, mostly provided by the RAF. HM Coastguard HMCG (now part of ...


4

I provided a potential mathematical solution on deriving the flight paths using the ACARS data on 17 March (before the possible flight paths were published by the authorities) on CNN's iReport: http://ireport.cnn.com/docs/DOC-1108312 The key to finding MH370 without the aid of the transponder data but with regular attempted ‘handshakes’ from the ACARS ...


4

As of 2017 191 of the 193 countries are signed to the ICAO anex and there are 122 national aviation authorities so at least some countries lack serious formal aviation authority and often look to other nations for help. Smaller, war torn nations or nations that do not have the facilities of first world countries may simply not have any ability to provide SAR ...


3

Yes, it's certainly possible. But it all depends on a lot of factors. Speed of impact. Obviously, the lower the speed of impact the fewer pieces will break away. time. Even if things break away and float, after a while they'll sink as they become water logged. And that may only take minutes. environmental conditions. Water temperature affects the speed at ...


3

Actually it was during WW2 and it was the Pacific: One of Rickenbacker's most famous near-death experiences occurred in October 1942 [...] The bomber strayed hundreds of miles off course while on its way to a refueling stop on Canton Island and was forced to ditch in a remote and little-traveled part of the Central Pacific Ocean. I am not familiar with ...


3

Assuming that you've submitted a Delay Message in order to prevent your flightplan from being deleted you have to do nothing at all. In your flightplan you only state your ETD (Expected Time of Departure) and ETE (Estimated Time Enroute). Your ETA (Estimated Time of Arrival) will be calculated and relayed to all stations in need of the ETA by AIS (...


3

It happens ALL the time. I have been on many airport hunts looking for the airplane with a triggered ELT. You tale a handheld radio and walk through the ramp until you find it.


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