Prescott 3 departure

TheGolfPilot

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Yesterday I departed Prescott using the VCOA and when I was coming up on Drake and, thanks to a strong headwind, I was already through 9000 coming up on Drake so I asked if I could turn on course towards HEC VOR instead of making a climbing right turn back to Drake, the controller approved. My understanding, without ATC instructing otherwise, a right climbing turn would be required by the departure, unless continuing on V562, but the controller sounded like I was making an unnecessary request. Does anybody read the departure that you can continue on course at DRK if above 9000'? what wording are you looking at?
 
You met the 9000A requirement prior to DRK so there's no point in making a long right turn before turning on course.
 
You met the 9000A requirement prior to DRK so there's no point in making a long right turn before turning on course.
While I understand the logic, I share the OP’s confusion: the DP says “Aircraft departing on DRK VORTAC R-305 continue climbing on course. All other aircraft climbing right turn direct DRK VORTAC then on assigned course”, including for the VCOA. I’d personally do as he did, even at the risk of a sigh from ATC. Given your comment I was expecting to see something in the DP about being able to proceed on course once at 9000.

I’m open to learning here…
 
While I understand the logic, I share the OP’s confusion: the DP says “Aircraft departing on DRK VORTAC R-305 continue climbing on course. All other aircraft climbing right turn direct DRK VORTAC then on assigned course”, including for the VCOA. I’d personally do as he did, even at the risk of a sigh from ATC. Given your comment I was expecting to see something in the DP about being able to proceed on course once at 9000.
What would be the point of making a right 314° turn at DRK?

The R-305 to 9,000' is to allow slowly-climbing aircraft time to reach a safe altitude.
 
I can see the confusion, but if you're AT 9000 at DRK, you have already complied with the rest of the departure procedure. You already did "climb on DRK VORTAC R-305 to 9000" - you reached it on the 305 radial at 0 (zero) DME. You then need to "turn right direct DRK" - well you're already there. Then "on assigned course".

So I agree that the call to ATC was not necessary, but I also agree with asking the question if you're not sure. There are many, many departure procedures (and missed approach instructions) where the actual flying of it isn't very clear if you are in an airplane that can climb better than 200 ft per nm, which is how these procedures are designed. And of course, most airplanes CAN climb better than 200 ft per nm under most conditions.
 
What would be the point of making a right 314° turn at DRK?

The R-305 to 9,000' is to allow slowly-climbing aircraft time to reach a safe altitude.
I agree - which is why I’m confused it isn’t written as “…direct DRK VORTAC, then climb on DRK VORTAC R-305 to 9000 then proceed on course”. That’s what you’re saying is implied (and I agree it’s a sensible thing to do) but for some reason they added the right turn unless departing on R-305.

Add: It feels almost like doing an approach and clarifying if you’re cleared straight in or need to do the HILPT for an otherwise straight-in arrival. I’ve never understood the point of that either but if I don’t hear “cleared straight-in” (which I hear, typically), I confirm.
 
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Yesterday I departed Prescott using the VCOA and when I was coming up on Drake and, thanks to a strong headwind, I was already through 9000 coming up on Drake so I asked if I could turn on course towards HEC VOR instead of making a climbing right turn back to Drake, the controller approved. My understanding, without ATC instructing otherwise, a right climbing turn would be required by the departure, unless continuing on V562, but the controller sounded like I was making an unnecessary request. Does anybody read the departure that you can continue on course at DRK if above 9000'? what wording are you looking at?
The Controller might have had a tone to his voice wondering why doesn’t he just request direct Hector. Once he gives you direct Hector, the ODP ceases to exist. You go direct Hector, then he tells you to contact the Hector Sector Vector Director 128.15.:biggrin:
 
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So I agree that the call to ATC was not necessary, but I also agree with asking the question if you're not sure. There are many, many departure procedures (and missed approach instructions) where the actual flying of it isn't very clear if you are in an airplane that can climb better than 200 ft per nm, which is how these procedures are designed. And of course, most airplanes CAN climb better than 200 ft per nm under most conditions.
If a pilot on a IFR flight plan can make good the ODP climb gradient, the VCOA should be avoided. VCOAs are a great concept for poorly performing airplanes, but only at airports where the pilot has local knowledge.
 
If a pilot on a IFR flight plan can make good the ODP climb gradient, the VCOA should be avoided. VCOAs are a great concept for poorly performing airplanes, but only at airports where the pilot has local knowledge.
There was poor weather in the initial direction of the ODP I wanted to avoid. I chose to fly the VCOA because it allowed me to avoid most of the nasty stuff.
 
There was poor weather in the initial direction of the ODP I wanted to avoid. I chose to fly the VCOA because it allowed me to avoid most of the nasty stuff.
You could also request a VFR climb and deviate as necessary.
 
You could also request a VFR climb and deviate as necessary.
yes. It wasn't clear over drake either though. It was a pretty unique weather scenario the other day. It was clear over the airport. It was really bad south, and you weren't getting all the way to drake to 10k+ in VMC. If I wanted to depart vfr I either would have to box climb over the field to 12k or scud run about 50 miles west(an unknown). Do a left hand turn over the field to the airport then fly to Drake was ideal. I only went through a small cloud or two, didn't pick up any ice, and everyone in the back was enjoying a good ride.

That is besides the point though. I'd imagine most aircraft following the standard procedure are redirected by ATC well before Drake. Say a Turbojet departs on the PRC3 and gets to DRAKE at 17k feet. ATC is busy and hasn't gotten to him yet and his flightplan says PRC.DRK PMD, he turn left, straight to PMD. ATC won't care but what words in that departure say you can do that?
 
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yes. It wasn't clear over drake either though. It was a pretty unique weather scenario the other day. It was clear over the airport. It was really bad south, and you weren't getting all the way to drake to 10k+ in VMC. If I wanted to depart vfr I either would have to box climb over the field to 12k or scud run about 50 miles west(an unknown). Do a left hand turn over the field to the airport then fly to Drake was ideal. I only went through a small cloud or two, didn't pick up any ice, and everyone in the back was enjoying a good ride.

That is besides the point though. I'd imagine most aircraft following the standard procedure are redirected by ATC well before Drake. Say a Turbojet departs on the PRC3 and gets to DRAKE at 17k feet. ATC is busy and hasn't gotten to him yet and his flightplan says PRC.DRK PMD, he turn left, straight to PMD. ATC won't care but what words in that departure say you can do that?
If you are not for hire you can do whatever it takes so long as you aren't assigned the Winski 2. For hire, you have to fly one of the departures or a company procedure.
 
I agree - which is why I’m confused it isn’t written as “…direct DRK VORTAC, then climb on DRK VORTAC R-305 to 9000 then proceed on course”. That’s what you’re saying is implied (and I agree it’s a sensible thing to do) but for some reason they added the right turn unless departing on R-305.

Understand that the basic design of a departure procedure like this is still rooted in non-GPS, airway navigation. The idea is to design it so that the worst-equipped, VOR-only aircraft can still fly it, unless there is no other option.

So, for a VOR-equipped aircraft, they can't just proceed on course from some arbitrary point where they reach 9000 on the R-305. Rather, they'd have to return to the DRK VOR anyway to get on an airway. If they happen to be going along V562 (which is R-305) anyway, then they can just keep going.
 
yes. It wasn't clear over drake either though. It was a pretty unique weather scenario the other day. It was clear over the airport. It was really bad south, and you weren't getting all the way to drake to 10k+ in VMC. If I wanted to depart vfr I either would have to box climb over the field to 12k or scud run about 50 miles west(an unknown). Do a left hand turn over the field to the airport then fly to Drake was ideal. I only went through a small cloud or two, didn't pick up any ice, and everyone in the back was enjoying a good ride.

That is besides the point though. I'd imagine most aircraft following the standard procedure are redirected by ATC well before Drake. Say a Turbojet departs on the PRC3 and gets to DRAKE at 17k feet. ATC is busy and hasn't gotten to him yet and his flightplan says PRC.DRK PMD, he turn left, straight to PMD. ATC won't care but what words in that departure say you can do that?

First, I agree with the other posters here — you were good, and there was no need to ask ATC, however noone ever got in trouble who asked for confirmation (and you should just ignore any annoyed sounds from ATC who is comfortably down on the ground drinking coffee).


I really like how you evaluated all your options and picked what you saw as the best. Talk about expert ADM — well done.


One small nit-pick about terminology. You started your question asking about VCOA. This is a manuever that requires you maintain VFR. You mentioned passing through one or two clouds on the way to altitude. That would be a no-no.


But the rest of your question referred to tou asking about the Prescott 3 ODP — which is an IFR procedure, and you are permitted to enter IMC. Not a big deal, just terminology.
 
One small nit-pick about terminology. You started your question asking about VCOA. This is a manuever that requires you maintain VFR. You mentioned passing through one or two clouds on the way to altitude. That would be a no-no.

But the rest of your question referred to tou asking about the Prescott 3 ODP — which is an IFR procedure, and you are permitted to enter IMC. Not a big deal, just terminology.

At this airport, the Prescott 3 is the default ODP, and the VCOA is an option listed on the Prescott 3 itself. The VCOA and the non-VCOA options both end up intercepting the R-305 to the DRK VOR, after that they are identical.

The VCOA only requires visual conditions up to 6700 MSL, or a ceiling of 1800. After that you can be in the clouds. If the OP did enter the clouds below 6700 then that is certainly incorrect, however that's not entirely clear from the posting, although he does say it was "clear over the airport".
 
First, I agree with the other posters here — you were good, and there was no need to ask ATC, however noone ever got in trouble who asked for confirmation (and you should just ignore any annoyed sounds from ATC who is comfortably down on the ground drinking coffee).


I really like how you evaluated all your options and picked what you saw as the best. Talk about expert ADM — well done.


One small nit-pick about terminology. You started your question asking about VCOA. This is a manuever that requires you maintain VFR. You mentioned passing through one or two clouds on the way to altitude. That would be a no-no.


But the rest of your question referred to tou asking about the Prescott 3 ODP — which is an IFR procedure, and you are permitted to enter IMC. Not a big deal, just terminology.
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The VCOA and the non-VCOA options both end up intercepting the R-305 to the DRK VOR, after that they are identical.

Actually, they both end up intercepting the DRK R-305 AFTER PASSING the VOR; one must be northwest of the VOR to track that radial, coming or going. If one is tracking 305 to the VOR, they’re tracking inbound on R-125. So, as depicted and regardless of the altitude one has reached, we’re to cross the VOR before the next step.

And the chart shows either to go straight ahead or do a right turn after 9000 on R-305.

Again, I get the head-scratch about making a big right turn or even asking about it but my ISTJ personality won’t let me assume I can do it, just like proceeding straight in on an approach showing a HILPT. I can say with confidence I won’t get a phone number for asking for clarification. Not asking might…
 
Actually, they both end up intercepting the DRK R-305 AFTER PASSING the VOR; one must be northwest of the VOR to track that radial, coming or going. If one is tracking 305 to the VOR, they’re tracking inbound on R-125. So, as depicted and regardless of the altitude one has reached, we’re to cross the VOR before the next step.

And the chart shows either to go straight ahead or do a right turn after 9000 on R-305.

Again, I get the head-scratch about making a big right turn or even asking about it but my ISTJ personality won’t let me assume I can do it, just like proceeding straight in on an approach showing a HILPT. I can say with confidence I won’t get a phone number for asking for clarification. Not asking might…
Pretty sure he meant from instead of to. "... intercepting the R-305 to the DRK VOR..." just doesn't even figure into the scenario.
 
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