Deoarture clearance change
 

Hi

Is there any guidelines on how late a departure clearance can be changed to a more complicated and involved procedure.

Had a simple Rwy heading to 4000' originally given to us on stand but then when lined up on a active rwy given a more involved significantly more challenging published SID.

If you have official reference then that would be most helpful.

Regards

Pin

A/C: XYZ Ready.
ATC: XYZ Line Up, Recleared the Complex1A departure.
A/C: Recleared the Complex1A departure, not ready, holding position XYZ.

Airmanship, sorry don't have a reference for that.

My own words,

Towermanship -airmanship for [tower] controllers

Why? Do you have problem if ATC amend your departure on safety grounds?

I think Pin has a valid point.
Having watched crews go through a SID briefing, it's not something you want to do when lined-up. Had the controller indicated that there was no immediate inbounds that would ease the pressure on the crew to complete the briefing, even then the presence of further pending departures behind Pin's a/c could easily result in the SID briefing being rushed.
This is the kind of scenario often encountered in CHIRP.

I also think he's got a valid point. Perhaps any pilots loitering here (Pin Head incl.) could give us an idea of what a SID change might involve? I've had pilots complain about a change of runway / SID which has required them to reprogram FMC or rebrief for at least a couple of minutes, and that's before taxi. I'd be extremely loath to force them into that on an active runway.
And a change from a heading to a SID doesn't sound like a last minute safety issue, more like the lifting of a previous restriction back to standard ops (assuming that the airport usually uses SIDs).

Hi

Lined up an active runway.
Arriving aircraft in the vicinity
All briefings and checklists complete
Due a slot, 60mins since previous clearance given inc 20mins at the holding point
New significantly more involved clearance given with various hard heights and sod restictions

Honesty is the best policy! Advise controller that it will take at least two minutes to set up and brief the new clearance. In ATC terms that feels like an hour,especially if you're lined up.
A couple of observations I could make. The original clearance seems like a cop-out from a controller who didn't know what to say an hour before...the clearance seems to be a tactical solution which could not possibly have been identified so early. Second...how often do you see controllers on the flight deck these days? Third...Some modern controllers have very little interest in the job other than the £100k salaries, they might not actually realise the enormity and significance of their actions in a case such as yours.
Solution....Stay cool.....absolute must is to put the details in voyage report or feedback to chief pilot/liaison/OPS or whatever you use. Process locally might work...but a paper trail through to relevant regulatory authority such as UK CAA is always advisable.....your experience can help everybody.
Just a question for you.....an assigned heading is only good for maybe three minutes [in the event of radio-fail] ...what would you have done after that? I guess an option would have been to revert to the most appropriate SID.

A change of SID can have other consequences. On the A320, if you put a new SID in the FMGC, your performance (speeds and flex temp) will drop out on the PERF page. Not really what you want when on the runway with someone on the approach behind you. Conversely, changing a SID to a "climb straight ahead to x thousand feet" should not be a big deal for anyone.

Chevvron....did you read the bit about the acft being lined up on the runway? Unless your next inbound isn't due for 10 minutes or so I can't see why the original clearance couldn't stand or at least be replaced (if absolutely necessary) with something just to get him going. And if it's that busy that a SID has to replace a heading and altitude....why not just issue the SID in the first place.

Maybe some unpredicted traffic got in the way during taxy, so the departure controller, having originally tried to cut corners, reverted to sop.
My main experience is operating IFR in class G airspace where it is always wise to have a 'plan B' in mind when issuing a departure clearance.

From memory, and I may be wrong, or it might have changed, but SIDs weren't applicable in class G in the UK. And in CAS it was standard practice to issue a SID on clearance request which the Approach controller could amend to a heading prior to departure. I never saw it the other way round. Maybe the OP could help us by telling us where this happened.

True for UK civil airfields in class G, but UK Mil airfields do publish SIDs in class G

Just occured to me to ask what classification was the airspace you were departing into?