5 ms·

Just a wild guess: Could the enterprise in-house code signing certificate have expired? That would lock out the app. Imagine that happening mid-flight! (The iO

by 0x0 12y ago

Just a wild guess: Could the enterprise in-house code signing certificate have expired? That would lock out the app. Imagine that happening mid-flight! (The iOS enterprise in-house code signing certificates, which only Apple can issue, always seem to come with 1-2 year hard expiration dates)

ceejayoz 12y ago
> Imagine that happening mid-flight! Not a problem, really. FAA regulations require all sorts of backups and emergency procedures. Even my dad's little four-seat general aviation plane has backups for every critical instrument. This issue prevents you from taking off (out of caution), but if it happened in-flight everyone'd know what to do.
- wodenokoto 12y ago
  More over, isn't this just a manual? I mean, for most normal situations, the pilots know what to do, so even if the backup also died, chances are pretty good that they would land without problems, I imagine.
  - k-mcgrady 12y ago
    I thought it was the flight plan.
    - rpmcb 12y ago
      The flight plan is programmed into the airplane's avionics, as well as on a printed hard copy in the cockpit. The app is supplemental. It can not be used as a primary navigation reference, per FAA regulations.
      - blktiger 12y ago
        It sounded to me like the pilot's couldn't input the flight plans into the cockpit avionics because they didn't have a paper copy of the flight plan.
        rpmcb 12y ago
        A flight plan and a procedure are very different things. Every commercial flight in America has a hard copy of their flight plan in the cockpit.
  - ams6110 12y ago
    There are so many possible scenarios that are encountered in flight that there is no way to have them all memorized. There are certain "memory items" that a pilot must know, but many procedures for dealing with both routine and emergency problems require the non-flying pilot to pull out a quick-reference handbook or checklist to be sure everything is done in the proper order and nothing is overlooked. Even routine departures and landings follow a checklist.
    - Someone1234 12y ago
      A lot of newer aircraft have built in checklists now[0]. For a bunch of reasons (e.g. safety, automatic double-checking, and expedience). Yes, it would be non-optimal if an aircraft had an issue without a handbook, but assuming that communications haven't been lost, someone on the ground can easily read out items. [0] http://www.boeing.com/news/frontiers/archive/2006/april/i_ca3.html http://www.boeing.com/news/frontiers/archive/2006/april/i_ca...
      - cnvogel 12y ago
        ...so what's the checklist to mitigate the situation "the monitor which normally displays the checklist on this airplane failed"... :-)
  - VLM 12y ago
    Maps too, from what I hear. The problem is scalability. If no one carried maps, everyone would have to talk verbally and take notes with ATC for five minutes for every landing to make sure nothing had changed. If only a couple planes pester ATC then the system will keep up. It would be safe enough. What are the odds of an inflight emergency requiring a diversion at any instant? Pretty low. So if it happened to one plane they'd figure it out verbally. However requiring all ATC and all pilots to talk over all maps at all landings isn't scalable. Something similar happens with manuals. One plane loses a system and its ipad, you call home on the radio or satphone or contact a fellow pilot on 123.45 MHz or call ATC for help. This doesn't scale to every plane in the air at the same time for every mostly minor maintenance writeup. Maybe you can ignore error messages this flight, after all most measurable things are not important, just like in business. Or maybe engine code 3141Z.kjdf.subsection2 means the engine is about to explode on the wing, but you've got no manuals... Something often overlooked is megacorp analysis paralysis. You'll be formally written up if you don't file an engine operation temperature profile thingy form or some meaningless catering receipts or whatever according to boring corporate policy, and it will be brought up at your annual performance review, affect your promotion chances, etc. This scales pretty well when one ipad breaks and you use the copilots ipad or call your boss and argue and he issues you an indulgence or the boss takes dictation of the form for you or you refuse to fly (its only one flight after all). This doesn't scale well when every ipad in a company stops working. Personally, if I were in a plane over water and I lost all my papers out the window, no fuel estimates, no weight and balance, no maps, no flight plan, no list of obstacles, no nav plan, no notes, nothing at all, I'd probably panic and head for the closest coastal airport (and where is that, without any docs?) If one plane does this, it scales VERY well. ATC calms you down, vectors you in, gives you some geographical advice, and you land. If every plane in the air does this simultaneously, you'll overload ATC and probably get someone killed. This applies everywhere to all industries not just planes.
    - phdp 12y ago
      Charts, not maps ;)
      - innguest 12y ago
- mikeash 12y ago
  Your last sentence is key, and seems to be something that everybody forgets about. You have a great deal of redundancy so that a problem in the air doesn't get you killed. But the whole point of that redundancy is defeated if you're relying on it from the beginning of the flight. Therefore it's common, and reasonable, to have issues that wouldn't cause any trouble in the air, but which prevents you from flying to begin with. Imagine if the speedometer in your car failed. You shouldn't drive it until you get it fixed, but it won't kill you if it happens while you're on the highway.
- cnvogel 12y ago
  Normally you reach a decision on the kind of redundancy and technological diversity by looking at certain risks and then decide if you only need one, two of the same, or two or more of differently implemented/built devices using different methods of operation. For (made up example, I don't know anything in particular about aviation, but know the general approach from working with controls for nuclear powerplants) navigation one might conclude that GPS and old-fashioned UHF radio navigation is technologically different enough that an event taking down one means of navigation (say, jamming of GPS at 1.5 GHz, spread spectrum, digital, ...) will not affect UHF radio (at analog modulation on a few hundred MHz). So one decides that you have GPS and UHF, displayed on different monitors/indicators, powered by separate power-busses in the airplane. For paper documentation, they'll probably claim: Bring two binders with the procedures to the plane, store at different sides of the cockpit. For iPads one might have decided that they must not be connected to any network while on the plane, so that data cannot be deleted from the pilot's and first officer's devices. But have they considered the "common cause failure" of two iPads, not being connected to any network, not communicating with each other, with full batteries, probably with passed selfchecks (checksums for stored data on the flash)... to really fail at the same time because of an expired certificate?
k-mcgrady 12y ago
I hope there isn't a guy sitting somewhere who accidentally rejected the certificate :) I think that also locks everyone out. If the iPad's all crashed though it seems unlikely. Although it's definitely something that could be easily missed.
- 0x0 12y ago
  Ah, but when you read stories like this, I wouldn't trust the reporter (or even the interviewee) to be 100% accurate. "All crashed" could mean anything from a dead battery to being PIN locked to failure to launch because of an expired code signing cert :P
  - k-mcgrady 12y ago
    Good point and definitely possible. In fact I've done it myself - switched computer rejected the old certificate and suddenly nobody could access the app. Fortunately at the time it was only a few people and a beta so not too big of a problem.
ryanmarsh 12y ago
Nothing in AA IT would surprise me. I did some contracting there. Their technology groups are so horribly f'ed up. The only client I've had worse was the government.
hellbanner 12y ago
The VPP certificates never expire though, right?

by 0x0 12y ago

ceejayoz 12y ago

> Imagine that happening mid-flight! Not a problem, really. FAA regulations require all sorts of backups and emergency procedures. Even my dad's little four-seat general aviation plane has backups for every critical instrument. This issue prevents you from taking off (out of caution), but if it happened in-flight everyone'd know what to do.

wodenokoto 12y ago
More over, isn't this just a manual? I mean, for most normal situations, the pilots know what to do, so even if the backup also died, chances are pretty good that they would land without problems, I imagine.
- k-mcgrady 12y ago
  I thought it was the flight plan.
  - rpmcb 12y ago
    The flight plan is programmed into the airplane's avionics, as well as on a printed hard copy in the cockpit. The app is supplemental. It can not be used as a primary navigation reference, per FAA regulations.
    - blktiger 12y ago
      It sounded to me like the pilot's couldn't input the flight plans into the cockpit avionics because they didn't have a paper copy of the flight plan.
      - rpmcb 12y ago
        A flight plan and a procedure are very different things. Every commercial flight in America has a hard copy of their flight plan in the cockpit.
- ams6110 12y ago
  There are so many possible scenarios that are encountered in flight that there is no way to have them all memorized. There are certain "memory items" that a pilot must know, but many procedures for dealing with both routine and emergency problems require the non-flying pilot to pull out a quick-reference handbook or checklist to be sure everything is done in the proper order and nothing is overlooked. Even routine departures and landings follow a checklist.
  - Someone1234 12y ago
    A lot of newer aircraft have built in checklists now[0]. For a bunch of reasons (e.g. safety, automatic double-checking, and expedience). Yes, it would be non-optimal if an aircraft had an issue without a handbook, but assuming that communications haven't been lost, someone on the ground can easily read out items. [0] http://www.boeing.com/news/frontiers/archive/2006/april/i_ca3.html http://www.boeing.com/news/frontiers/archive/2006/april/i_ca...
    - cnvogel 12y ago
      ...so what's the checklist to mitigate the situation "the monitor which normally displays the checklist on this airplane failed"... :-)
- VLM 12y ago
  Maps too, from what I hear. The problem is scalability. If no one carried maps, everyone would have to talk verbally and take notes with ATC for five minutes for every landing to make sure nothing had changed. If only a couple planes pester ATC then the system will keep up. It would be safe enough. What are the odds of an inflight emergency requiring a diversion at any instant? Pretty low. So if it happened to one plane they'd figure it out verbally. However requiring all ATC and all pilots to talk over all maps at all landings isn't scalable. Something similar happens with manuals. One plane loses a system and its ipad, you call home on the radio or satphone or contact a fellow pilot on 123.45 MHz or call ATC for help. This doesn't scale to every plane in the air at the same time for every mostly minor maintenance writeup. Maybe you can ignore error messages this flight, after all most measurable things are not important, just like in business. Or maybe engine code 3141Z.kjdf.subsection2 means the engine is about to explode on the wing, but you've got no manuals... Something often overlooked is megacorp analysis paralysis. You'll be formally written up if you don't file an engine operation temperature profile thingy form or some meaningless catering receipts or whatever according to boring corporate policy, and it will be brought up at your annual performance review, affect your promotion chances, etc. This scales pretty well when one ipad breaks and you use the copilots ipad or call your boss and argue and he issues you an indulgence or the boss takes dictation of the form for you or you refuse to fly (its only one flight after all). This doesn't scale well when every ipad in a company stops working. Personally, if I were in a plane over water and I lost all my papers out the window, no fuel estimates, no weight and balance, no maps, no flight plan, no list of obstacles, no nav plan, no notes, nothing at all, I'd probably panic and head for the closest coastal airport (and where is that, without any docs?) If one plane does this, it scales VERY well. ATC calms you down, vectors you in, gives you some geographical advice, and you land. If every plane in the air does this simultaneously, you'll overload ATC and probably get someone killed. This applies everywhere to all industries not just planes.
  - phdp 12y ago
    Charts, not maps ;)
    - innguest 12y ago
mikeash 12y ago
Your last sentence is key, and seems to be something that everybody forgets about. You have a great deal of redundancy so that a problem in the air doesn't get you killed. But the whole point of that redundancy is defeated if you're relying on it from the beginning of the flight. Therefore it's common, and reasonable, to have issues that wouldn't cause any trouble in the air, but which prevents you from flying to begin with. Imagine if the speedometer in your car failed. You shouldn't drive it until you get it fixed, but it won't kill you if it happens while you're on the highway.
cnvogel 12y ago
Normally you reach a decision on the kind of redundancy and technological diversity by looking at certain risks and then decide if you only need one, two of the same, or two or more of differently implemented/built devices using different methods of operation. For (made up example, I don't know anything in particular about aviation, but know the general approach from working with controls for nuclear powerplants) navigation one might conclude that GPS and old-fashioned UHF radio navigation is technologically different enough that an event taking down one means of navigation (say, jamming of GPS at 1.5 GHz, spread spectrum, digital, ...) will not affect UHF radio (at analog modulation on a few hundred MHz). So one decides that you have GPS and UHF, displayed on different monitors/indicators, powered by separate power-busses in the airplane. For paper documentation, they'll probably claim: Bring two binders with the procedures to the plane, store at different sides of the cockpit. For iPads one might have decided that they must not be connected to any network while on the plane, so that data cannot be deleted from the pilot's and first officer's devices. But have they considered the "common cause failure" of two iPads, not being connected to any network, not communicating with each other, with full batteries, probably with passed selfchecks (checksums for stored data on the flash)... to really fail at the same time because of an expired certificate?

k-mcgrady 12y ago

I hope there isn't a guy sitting somewhere who accidentally rejected the certificate :) I think that also locks everyone out. If the iPad's all crashed though it seems unlikely. Although it's definitely something that could be easily missed.

0x0 12y ago
Ah, but when you read stories like this, I wouldn't trust the reporter (or even the interviewee) to be 100% accurate. "All crashed" could mean anything from a dead battery to being PIN locked to failure to launch because of an expired code signing cert :P
- k-mcgrady 12y ago
  Good point and definitely possible. In fact I've done it myself - switched computer rejected the old certificate and suddenly nobody could access the app. Fortunately at the time it was only a few people and a beta so not too big of a problem.

ryanmarsh 12y ago

Nothing in AA IT would surprise me. I did some contracting there. Their technology groups are so horribly f'ed up. The only client I've had worse was the government.

hellbanner 12y ago

The VPP certificates never expire though, right?