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Departure


Guest BigSkyGuy

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Guest BigSkyGuy

Question fo jet drivers. Given the choice, would you rather climb unrestricted to FL250 and be vectored 15-20 miles off course, or get on course immediately, and stopped at 6,000' AGL for 5-7 minutes. All restrictions due to arrival traffic.

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Niether.

Seven minutes seems like a long time to be held at 6000'. Also, FL250 and 20 miles off course seem extreme.

All arrivals enter the TCA [YYZ] via the STAR. As far as I'm concerned, a 20 mile vector on departure is a sign of an inefficiency, wouldn't you agree?

However, to answer your question, would depend on many factors, met, wind, rides etc. All things being equal, I'd prefer a direct to the FIR boundary, levelling for traffic when required.

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All things being equal gimme the altitude first. Higher TAS and lower fuel burn. However sometimes the off course vector to the high altitude is a turn into a high headwind and the on-course hdg and altitude below 10,000 would be more favourable.

Most time I think Alt first is best...

Cheers chico

PS great topic away from the usual bs...

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Guest caevans

An unrestricted climb to FL250 would be my choice. I could average at least 6 miles per minute to FL250 and eat a 20 mile off-course (I'm assuming linear) in less than three and a half minutes of air time, not to mention the lower specific fuel consumption at the higher altitudes. In certain weather conditions, the climb would be most desireable. Glad to see someone asking this question.

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Hiya BSG: In general, I too would prefer the unrestricted climb. The word "itchy" was used below to describe 250 @ 6000' for that long. It's not so much the fuel penalty as the "anticipation" of seeing and avoiding VFR traffic, low level turbulence in the case of bad weather, and those darn feather-winged creatures we tend to encounter from time to time.

Guess it really depends on a lot of factors - how much of an off-course vector did you have in mind? 90 degrees? More?

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Guest Say Again

Would you prefer 250-270 knots for 40 miles or a 30 degree turn for 15 miles then back towards the on course at regualr speed?

FX

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If the target is crossing a specific point at a specific time, probably the best thing would be the speed adjustment. Going slower saves fuel.

If it's for crossing traffic, and there are no downline time-based crossing restrictions, it's probably a wash. As close as I can figure, each of the options you suggest eats the equivalent of about 2 1/2 minutes. If it's outbound, I'd guess the vector would be better because a subsequent direct would mean you don't eat the cost on returning to the oncourse ... inbound... the speed would be better because you probably have to mirror the vector returning to the oncourse.

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My vote is altitude first, for safety as much as fuel burn. Birds, turbulence, icing, traffic density, etc, etc.

I don't know if there is an option between 6000 and 250, say above 10000 and only 10 miles off course. Getting above 10 solves a lot of the problems I noted above and allows us to pick up the speed, especially handy at high weights on aircraft like the B747, which has limitations on ice protection with the slats out.

Good thread. I'd sure like to see more of this kind of stuff here.

Vs

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Working departure, we're often faced with the keep climbing VS level-off but on course dilema. Over the years, I've found that 90% of the time, it's best to keep the jets climbing, while the props will be turned on course, and kept lower for traffic. Works for me, works for the crews.

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