IFR Clearance Altitude vs ODP Altitude

[ngoiz]

Hi there,

I was flying to day IFR out of IZA and got cleared as filed with an initial altitude to maintain of 5000. Since wx was not great I opted for the ODP that states the following DP instruction:

Rwy 26, climb heading 264° to 6000, intercept GVO VORTAC R- 307 to ORCUT INT/MQO 30.00 DME.

Therefore, since my ATC cleared altitude was lower than the ODP altitude I was slightly confused. Unfortunately the frequency was really busy at the time and couldn't find a break to ask, but also knowing that as soon as I got ID'd I'd get a higher altitude I didn't give it much thought after that and flew with the mindset of maintaining 5000 as per ATC's instruction.

For the next time what would be the correct procedure? My guess would be that an ATC assigned altitude goes before what's stated on the ODP. On the other hand, if an ODP has an altitude to climb to its obviously for obstacle clearance.

Any comments appreciated

Thanks!

[jx_]

That's not what the ODP is saying. When an ODP says "climb on procedure A to altitude Y, then do procedure Z" it is not safe to do Z until reaching the altitude Y. Procedure A is safe if you make the minimum climb rate for the procedure.

In your case, heading 264 is safe if you make the minimum climb rate for the procedure. You could stay on that heading for a long time (all the way across the Pacific!)


ATC assigns protected initial altitudes that are synced with the ODP. If the ODP has a hold/heading/procedure that has an altitude restriction, do not proceed past that point until meeting that requirement.

For example, if an ODP says "fly heading 100 to intercept XYZ 200 radial, climb to 4000 then direct YYY; Northbound on V123: cross YYY at or above 5000; and ATC assigns 3000.

You are safe at 3000, but stuck on the XYZ 200 radial until reaching 4000

You are safe at 4000, but will need to either: hold, reference the IFR chart to ensure compliance, or get ATC assistance (radar guidance) before proceeding northbound on the airway until reaching 5000.


So the answer is both apply. The initial altitude will be safe up until any restrictive point on the procedure. If ATC instructs you to continue beyond this restriction while below that altitude, they are watching you on the radar and will either climb you or issue an expected time to start climb. If ATC does not give specific instructions, then you must abide by the published procedure as written.

[ngoiz]

Brilliant, that clarifies it.

Many thanks for the detailed response