Let’s suppose I wish to fly an IFR flight from KTUS (Tucson International Airport) to KFST (Fort Stockton-Pecos) for example. Given the surrounding terrain there is of course an ODP that reads as follows:

DEPARTURE PROCEDURE: Rwys 3, 29L/R, climbing right turn direct to TUS VORTAC …
Rwy 21, climbing left turn direct to TUS VORTAC …
Rwy 11L/R, climb heading 123° to 4000 then climbing left turn direct TUS VORTAC …
... Climb in TUS VORTAC holding pattern (hold NW, right turns, 128° inbound) to 9000 before proceeding on course.

That’s a pretty long departure procedure especially with the temperatures this time of year but it makes perfect sense due to the terrain.

Now since I expect the weather to be CAVOK until the MSA, I would prefer to do a VFR climb-out. In this case, would I present myself as a regular VFR traffic to clearance, ground and tower frequencies and request IFR once at MSA to Center, or would I request an IFR clearance on ground and add the request for VFR climb-out up to the MSA?


KTUS doesn't have a VCOA, but I can think of a couple of alternatives (other people may have more). First, file a composite (VFR to IFR) flight plan. See the AIM section 5-1-7:

Flight plans which specify VFR operation for one portion of a flight, and IFR for another portion, will be accepted by the FSS at the point of departure. If VFR flight is conducted for the first portion of the flight, pilots should report their departure time to the FSS with whom the VFR/IFR flight plan was filed; and, subsequently, close the VFR portion and request ATC clearance from the FSS nearest the point at which change from VFR to IFR is proposed.

Second, depart VFR and ask for a pop-up IFR clearance when you need it. But this isn't ideal if you know that you'll be in IMC (or in the flight levels) at some point and you want to make sure your clearance isn't delayed.

Third, depart IFR and just ask ATC for whatever handling and routing you want. If weather conditions are good and there isn't much traffic, there's a good chance they'll let you do what you want. Considering the terrain, though, I wouldn't do it unless you're familiar with the area. And of course there's a chance that ATC won't allow it anyway.

Finally, although this doesn't answer the question you could just fly the ODP. I've never been to Tucson but the airport elevation is 2643' and right now the temperature is 32C and the altimeter setting is 30.10, that means the density altitude is about 5000'. And since you're departing to the east (more or less) it looks like you'll need to get to at least 11000' (IFR altitude) because of terrain, so you have to climb 8000' with limited space to do it and with reduced performance because of the high DA.

I don't know what you fly, but climb performance in those conditions isn't great in many light piston aircraft - at least if they're normally aspirated - and a climb in the hold seems like a good way to get up there safely. Of course, if you know the area well and your aircraft is up to it, then things would look different.

  • $\begingroup$ Thanks for the great answer ! Very complete and very helpful :) $\endgroup$ – Antoine Benkemoun Jun 22 '16 at 13:13
  • 1
    $\begingroup$ You don't need to do any of that. Just file IFR, and ask for a VFR climb on course when you pick up your IFR clearance on the ground. $\endgroup$ – Ralgha Sep 8 '20 at 3:20

The ODP is basically a VCOA if you draw out the hold you will see you are holding directly above the airfield.

Tucson does not want you flying the ODP if they have radar contact. They will provide vectors keeping you above their minimum vectoring altitudes (MVA). This means your course may be erratic or you may be wondering why they gave you that heading.

Another option is to depart IFR and when in contact with departure ask to go direct to your airway and you will "provide your own obstacle separation" or somethg similar to that. That relieves ATC from keeping you above the MVAs and they will allow you to proceed on your own course to the airway.

I've been to Tucson numerous times and this is what pilots do.

  • $\begingroup$ Thank you for your answer :) I figured that ATC would not want an airplane to fly the ODP by default so your second option sounds good ! $\endgroup$ – Antoine Benkemoun Jun 22 '16 at 13:14

Or you can depart on a IFR flight plan and when airborne request a "VFR climb to ___ (terrain plus 1000 feet or 2000 in mountainous terrain or MVA). You have now accepted responsibility for terrain clearance. The controller will still vector you for traffic seperation.

  • $\begingroup$ This is actually the correct answer according to the OP's question. $\endgroup$ – Ralgha Sep 8 '20 at 3:19
  • $\begingroup$ When I asked some ATC folks, they said to request the VFR climb when picking up your clearance on the ground, not after you’re already airborne. $\endgroup$ – StephenS Sep 8 '20 at 15:46

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.