117 flight time limit?

planejay

Well-Known Member
According to table A you are limited to nine hours of flight time, duty time is not an issue. You have flown three of four legs, actual flight time from the first three legs plus scheduled flight time for the fourth equals 8:36. You are obviously completely legal to finish the trip in this case. Now lets assume that the weather at the final destination is such that you require an alternate, planned flight time from the scheduled destination to the alternate is :36. Does this :36 need to be included in the planned flight time for the fourth leg since the weather is forecasted and not "unknown" or is it simply the scheduled flight time from point A to B? What if there is a reasonable chance that you will not be able to land, for example dispatched using 3585? It makes sense that if there is weather enroute that requires a pre-takeoff reroute totalling more than :24 that you are a pumpkin but the others are less clear to me. References?
 
According to table A you are limited to nine hours of flight time, duty time is not an issue. You have flown three of four legs, actual flight time from the first three legs plus scheduled flight time for the fourth equals 8:36. You are obviously completely legal to finish the trip in this case. Now lets assume that the weather at the final destination is such that you require an alternate, planned flight time from the scheduled destination to the alternate is :36. Does this :36 need to be included in the planned flight time for the fourth leg since the weather is forecasted and not "unknown" or is it simply the scheduled flight time from point A to B? What if there is a reasonable chance that you will not be able to land, for example dispatched using 3585? It makes sense that if there is weather enroute that requires a pre-takeoff reroute totalling more than :24 that you are a pumpkin but the others are less clear to me. References?


No. Read the rest of 117. You may be a pumpkin if you divert, but not by the intent of 117. Original schedule works by table? It also works with your PLANNED destination provided the route merits 117 table limits.
 
No. Read the rest of 117. You may be a pumpkin if you divert, but not by the intent of 117. Original schedule works by table? It also works with your PLANNED destination provided the route merits 117 table limits.
Perhaps I was a little unclear in my post or I am not completely understanding yours. The first part of mine is the scenario. I was curious if, assuming an alternate is required because of known weather, the flight time between the destination and the alternate must be considered when determining legality for takeoff. I have read 117 multiple times, which part are you suggesting I review? I understand that if a diversion happens on the last leg of my scenario that you are likely not legal to finish the trip due to the flight time limitations but if you exceed the limitation while airborne due to an unforeseen operational circumstance that you are legal.

Original schedule works by table?
I am not sure what is meant by this
 
If your original schedule works by 117, let's move to you being at the gate for the last leg. Do you meet 117 rules to go to the overnight by PLANNED flight time (inclusive of ground time)? If you are legal for point A to B, you can have an alternate, but that's now falls under extension language (call that point C).

An alternate is based on requirements to have an alternate, but not actually on planning to go to it under 117, as you need to be legal to dispatch under 121 for A to B. Point A to B legally is the plan, and the calculation, not the possibility of diverting to an alternate. That's where other language exists for extensions in the event you visit a point C.
 
(b) If unforeseen operational circumstances arise after takeoff that are beyond the certificate holder's control, a flightcrew member may exceed the maximum flight time specified in paragraph (a) of this section and the cumulative flight time limits in 117.23(b) to the extent necessary to safely land the aircraft at the next destination airport or alternate, as appropriate.
 
Even if you need an alternate, (or 2 under 3585), the forecast at your destination is still at or above minimums, so the expectation is that you will get in. If you can't, it's an unforeseen (but planned for - hence the alternate) operational circumstance that arose after takeoff. Just because you plan for the worst doesn't force it into becoming a "foreseen circumstance".
 
Even if you need an alternate, (or 2 under 3585), the forecast at your destination is still at or above minimums, so the expectation is that you will get in. If you can't, it's an unforeseen (but planned for - hence the alternate) operational circumstance that arose after takeoff. Just because you plan for the worst doesn't force it into becoming a "foreseen circumstance".
The weather tanking enroute is almost certainly an unforeseen circumstance that would authorize you to exceed the cumulative limits to the extent necessary to land. (I mean, what else are you going to do?)
 
Duty/Flight time rules are exactly like reserve fuel, they are primarily for planning and everyone knows that sometimes stuff happens in the air that will screw up "Plan A"

Once you take off, it is not a violation to use your reserve fuel to get safely on the ground (that's what it's for) nor is it a violation to fly past your allowable duty time if you had to hold or divert.
 
Thanks for the responses guys. I guess is what I am looking for is what would you consider a foreseen circumstance prior to takeoff? Bad enroute weather that the dispatcher has you planned through as opposed to around? (not uncommon at my shop where releases are built 4 hours prior and forgot about) There has been a big discussion about this around the playground, both sides having good arguments. Keep in mind this is for pre-takeoff flight time limits. The duty limitations and airborne exceptions are pretty clear.
 
Head to the back for a nap and assume everything will work itself out?

Sent from my XT1254 using Tapatalk
I was going to say something smart like "why would you bother to go to the back to nap," but thought it in poor taste.

Thanks for the responses guys. I guess is what I am looking for is what would you consider a foreseen circumstance prior to takeoff? Bad enroute weather that the dispatcher has you planned through as opposed to around? (not uncommon at my shop where releases are built 4 hours prior and forgot about) There has been a big discussion about this around the playground, both sides having good arguments. Keep in mind this is for pre-takeoff flight time limits. The duty limitations and airborne exceptions are pretty clear.
To me? Reports or forecasts, or a combination thereof, lead me to believe that a safe approach and landing cannot be made at the intended destination.

That is, "M1/4SM +TSRA (+TSSN, etc.)."

It's axiomatic in Fee For Departure 121 that the weather is always going to be good enough to dispatch - if the NWS doesn't say so, the "approved third-party vendor" will. That doesn't mean that you go to the destination and fly through it, necessarily. Indeed, it doesn't mean that you necessarily go at all. It'll be a cold day in hell before I make an admittedly tenuous FT/DT "foreseen vs. unforeseen operational circumstances" argument to the Captain (or MOD, should I be in the one in the left seat explaining why I am not loading the airplane up and going flying) over an absolute "this weather is crap, and we are not going to go fly into it, legal for dispatch or otherwise" argument.
 
Thanks for the responses guys. I guess is what I am looking for is what would you consider a foreseen circumstance prior to takeoff? Bad enroute weather that the dispatcher has you planned through as opposed to around? (not uncommon at my shop where releases are built 4 hours prior and forgot about) There has been a big discussion about this around the playground, both sides having good arguments. Keep in mind this is for pre-takeoff flight time limits. The duty limitations and airborne exceptions are pretty clear.

Foreseen is the big line of thunderstorms that is forcing ATC to re-route everyone and you get that re-route while you are sitting in line for departure. If that re-route would take you over your limits for the day, you're done.

Foreseen is getting an aircraft with an MEL restricting you to flight below 10,000ft through the Rockies and you need to re-route to avoid the high MEAs and that pushes you over the limits.

In your example of the dispatcher filing you through bad weather, I would argue that even though the dispatcher missed it or didn't follow up properly, you shouldn't have missed it and would have called before pushing off the gate to get a re-route and the fuel to go with it. That is what the FAA would expect too. Incompetence does not equal unforeseen.
 
Thanks for the responses guys. I guess is what I am looking for is what would you consider a foreseen circumstance prior to takeoff? Bad enroute weather that the dispatcher has you planned through as opposed to around? (not uncommon at my shop where releases are built 4 hours prior and forgot about) There has been a big discussion about this around the playground, both sides having good arguments. Keep in mind this is for pre-takeoff flight time limits. The duty limitations and airborne exceptions are pretty clear.

Foreseen is the big line of thunderstorms that is forcing ATC to re-route everyone and you get that re-route while you are sitting in line for departure. If that re-route would take you over your limits for the day, you're done.

Foreseen is getting an aircraft with an MEL restricting you to flight below 10,000ft through the Rockies and you need to re-route to avoid the high MEAs and that pushes you over the limits.

Foreseen is taxiing out for departure and then due to a prolonged ground stop, your total flight time for that leg (if you were to takeoff) would go over the limits.

In your example of the dispatcher filing you through bad weather, I would argue that even though the dispatcher missed it or didn't follow up properly, you shouldn't have missed it and would have called before pushing off the gate to get a re-route and the fuel to go with it. That is what the FAA would expect too. Incompetence does not equal unforeseen.
 
Back
Top