Are Obstacle DP's mandatory for Part 121 if you're IMC?

[BeechBoy]

Here's what the regs say in 91.175 (f):

(3) Except as provided in paragraph (f)(4) of this section, no pilot may takeoff under IFR from a civil airport having published obstacle departure procedures (ODPs) under part 97 of this chapter for the takeoff runway to be used, unless the pilot uses such ODPs.

(4) Notwithstanding the requirements of paragraph (f)(3) of this section, no pilot may takeoff from an airport under IFR unless:

(i) For part 121 and part 135 operators, the pilot uses a takeoff obstacle clearance or avoidance procedure that ensures compliance with the applicable airplane performance operating limitations requirements under part 121, subpart I or part 135, subpart I for takeoff at that airport;



I understand the first paragraph but am having difficulty with paragraph (4)(i), in particular the part about ensuring "compliance with the applicable airplane performance operating limitations requirements".

By the way, I'm not looking for a way to avoid ODP's. This question came up in an interview a friend of mine had with Skywest and when my friend answered that ODP's were mandatory the interviewer ripped him a new one and said that they "absolutely were not" mandatory.

Even though I don't have an aviation attorney on my speed dial to explain (4)(i) I think the reg clearly states that you need to have an authorized procedure for making sure you don't bump into things when you're taking off in instrument conditions.

[Doug Taylor]

At my airline, it's a certain hierarchy that we use and the priority goes like this:

• Departure Procedure in the 10-0 "Southernjets" Special Page(s).
• Radar departure or SID (DP) (as assigned by ATC).
• IFR Departure Procedure, (Obstacle DP), if published.
• Depart on course.

[AUAeropilot]

Originally Posted by Doug Taylor

At my airline, it's a certain hierarchy that we use and the priority goes like this:
• Departure Procedure in the 10-0 "Southernjets" Special Page(s).
• Radar departure or SID (DP) (as assigned by ATC).
• IFR Departure Procedure, (Obstacle DP), if published.
• Depart on course.

Ok, here's my FLOE interjection. The above is true in an all engine case. However in case of an...

Engine out:
• Departure Procedure in the 10-0 "Southernjets" Special Page(s).
• IFR Departure Procedure, (Obstacle DP), if published.
• When no Delta Runway Specific proc. or no IFR DP, initial climb will be
straight ahead until flaps are retracted or a safe maneuvering airspeed
is reached.

[Doug Taylor]

You mean after the confusion, the disbelief and the "Hey! Weren't we supposed to turn?"

[Cptnchia]

Originally Posted by Doug Taylor

You mean after the confusion, the disbelief and the "Hey! Weren't we supposed to turn?"

You left out the obligatory "OH S**T! Where is that plate?"

[B767Driver]

Most Part 121 operators ops specs will mandate that ODP are mandatory. As Doug stated...they might stipulate that SIDS, radar vectors or other special procedures take precedent over the ODP, however.

Originally Posted by BeechBoy

Here's what the regs say in 91.175 (f):

(3) Except as provided in paragraph (f)(4) of this section, no pilot may takeoff under IFR from a civil airport having published obstacle departure procedures (ODPs) under part 97 of this chapter for the takeoff runway to be used, unless the pilot uses such ODPs.

(4) Notwithstanding the requirements of paragraph (f)(3) of this section, no pilot may takeoff from an airport under IFR unless:

(i) For part 121 and part 135 operators, the pilot uses a takeoff obstacle clearance or avoidance procedure that ensures compliance with the applicable airplane performance operating limitations requirements under part 121, subpart I or part 135, subpart I for takeoff at that airport;



I understand the first paragraph but am having difficulty with paragraph (4)(i), in particular the part about ensuring "compliance with the applicable airplane performance operating limitations requirements".

By the way, I'm not looking for a way to avoid ODP's. This question came up in an interview a friend of mine had with Skywest and when my friend answered that ODP's were mandatory the interviewer ripped him a new one and said that they "absolutely were not" mandatory.

Even though I don't have an aviation attorney on my speed dial to explain (4)(i) I think the reg clearly states that you need to have an authorized procedure for making sure you don't bump into things when you're taking off in instrument conditions.

[AUAeropilot]

But you guys are a well trained machine, right? In all seriousness, I really got a feel for how busy it can get up front when we were doing the SXM sim eval. I just sat there and watched and wondered how much more confusion is added having the cabin call you every 2 seconds, "hey, did you hear that? hey, the engine stopped? hey, the passengers are wondering what's going on. etc.................."