PilotEdge Forums

Hi guys,

Just a little heads up on the CANOG1 Departure. There is a speed restriction that is not depicted on the SID and it is the
only departure out of VNY with a speed restriction. You'll hear in the clearance...."maintain 4000, expect FL...5 mins after
departure, departure freq 134.2, squawk ----, do not exceed 250 knots until advised." The controller makes sure the pilot
reads the 250 knots back to him.

Real world operations

Chris Allegro

Thank you. That's going to be tricky to incorporate into our SOP's, as we normally don't have to consult them very closely when a SID is involved, but if we can, we will. It sounds like they don't want them exceeding 250kts in the climb above 10k.

Hey Keith, yeah my guess would be that they don't want aircraft inflicting with traffic off of LAX on the CASTA2 RNAV, I'm pretty sure they fly right over the Valley, not sure of their altitude though.

Fascinating. I just spent 15 minutes pouring over the DP plates and the sectional, and then did a Google search for CANOG1. The speed restriction isn't mentioned anywhere. The CASTA2 out of LAX does share two common waypoints (CASTA and GMN) and the same general route of flight, but it looks like LAX departures would be at around 14,000 or higher by CASTA; VNY departures would probably be at more like 9,000-10,000 by CASTA. I don't see how a speed restriction helps much with sequencing departures out of LAX anyway -- it sure seems like altitude assignments would be much better tool for that.

What are typical climb airspeeds for jets above 10,000' ?

This is the sort of thing that really piques my curiousity -- why might the restriction exist?

-M.

Yep, you're correct, it isn't depicted, here is a link to the ground/clearance delivery frequencies, list to the clearances:
http://www.flykvny.com/aero/audio-recor ... 060001.mp3

We have a real world controller looking into this for us from the area, should have the answer soon, then we'll incorporate into our procedures (have discussed it with Peter, our Director of Operations & Quality Assurance).

What are typical climb airspeeds for jets above 10,000' ?

To answer this question. It's going to vary depending on a lot of factors, but as a data point for the CRJ-200 as operated by a large east coast regional airline: 250 to 10000' then 290 to a Mach .70 transition.

Thanks Peter. I'd have guessed the answer was about 280, so I was close. --and now this restriction makes even less sense to me, so I'm going to be really interested to hear the reason behind it (if we can ever figure it out).

I'd say it's all due to airspace size. There are a tonne of different flows in the area, and the slower you are, the tighter the turn will be, thus the controller will be able to better predict as to where you'll end up. I'd further say that this is more to do with center's workload, than departures'. Sector 4, which sits above the BUR area, is hella busy. Simpler forms of sequencing to some extent could have something to do with it too, considering the amount of traffic.

This was my guess in the email I wrote to the guy who's asking for us...

My wild guess is that it's issued because of the dissimilar jet aircraft types leaving VNY on that SID, where some jets might want to climb at 320 while others are still chugging at 250, or perhaps something to ease the merging of GMN DP's out of LAX with the deps out of VNY going to GMN or AVE, but other than that, I got nothin'! So, we thought we'd ask the guy who would know who to ask

The initial turns out of VNY are conducted below 10k, so they'll be at < 250kts in any case, but I suppose it could be due to the turning radius on subsequent course changes after they're > 10k, I hadn't thought of that.