Help reading a FAA departure procedure chart

Question

I was hoping to get a few answers regarding how to read a FAA departure procedure chart. Let's take the JUDTH SEVEN DEPARTURE chart shown below:

1. From what I can tell, it seems that the diagram in the upper left indicates that those taking off from either runway 3 or runway 21 should make an appropriate turn to heading 335 degrees. Is this correct?

2. Following the "thence...," it says to expect RADAR vectors to GBN VORTAC. So does this mean ATC will guide the aircraft to the GBN VORTAC fix?

3. Can someone explain what MOHAK TRANSITION (JUDTH7.MOHAK) means? Is this saying that the MOHAK fix represents a transition to en route airspace from terminal airspace?

4. How would one identify the departure fix in this chart and in general? Is the departure fix MOHAK? JUDTH? GILA? Additionally, what would be the departure procedure transition fix?

Thanks!

Answer 1

1. Yes, but (a) listen out for the 'Altitude cleared to' which will be given before departure since no 'top altitude' is published. (b) Depending on traffic, you may also be given a different heading from the published HDG335 (= "or as assigned by ATC")
2. "Expect radar vectors to GBS" means ATC will, after identifying you, give you vectors, and at some point give you a "cleared direct to GBS", remember this is an RNAV departure.
3. The leg between JUDTH and MOHAK is the Transition and ends at MOHAK, where presumably you will join your Airway.
4. I can say that the departure ends at JUDTH after which you are on the MOHAK transition that ends at MOHAK. Being an RNAV departure you have to be able to fly direct to any of these points by name and continue by following the ATC clearance. The controller will not use the term 'departure fix', it'll always be by name.

IF in doubt, get briefed by a regular, and you can always query ATC.

Answer 2

You have a good grasp on departures so far.

This particular SID advises the pilot departing Runway 3/21 to turn heading 335° and expect Radar Vectors to the GBN VORTAC. This is normal procedure considering the fact that so many airports in the same area share SIDs. Not all airports will have a co-located Navaid from which to start a SID. In this case, ATC would vector the aircraft back around the Phoenix airspace to GBN (Southwest) since the original 335° heading would be taking the aircraft away from GBN (due True North). Depending on traffic and ATC availability, ATC might vector you to the 249 Radial between GBN and JUDTH.

On other SIDs, there will be multiple fixes from which to leave the SID and transition to the en route portion of your flight. You, and/or ATC would file/assign for the fix most directly on your route of flight. In this case, there is only one, MOHAK.