In Ottawa, Ontario, Canada (CYOW), the Tower Controller usually give the instruction to the pilot to contact departures in the initial take-off clearance.
e.g. Tower Controller: Air Canada 453, contact Departures 1-2-8 decimal 1-7 when air borne, the wind is 280 at 8, clear for take-off.
I have noticed in many ATC clips found online for other airports where the Tower Controllers doesn't instruct the pilot to contact Departures until after the airplane has taken off.
My question is, are there other airports where the Controller give the "contact departures" instruction in the initial take-off clearance, similar to CYOW?
A number of times this happens at USAF facilities, at least here in the US. Section 3-9-3.a.2 of FAA JO 7110.65U explains this:
3-9-3. DEPARTURE CONTROL INSTRUCTIONS
Inform departing IFR, SVFR, VFR aircraft receiving radar service, and TRSA VFR aircraft of the following:
a. before takeoff:
2. Inform all departing IFR military turboprop/turbojet aircraft (except transport and cargo types) to change to departure control frequency. If the local controller has departure frequency override, transmit urgent instructions on this frequency. If the override capability does not exist, transmit urgent instructions on the emergency frequency.
CHANGE TO DEPARTURE.
3. USAF. USAF control towers are authorized to inform all departing IFR military transport/cargo type aircraft operating in formation flight to change to departure control frequency before takeoff.
Other times in the US, the call to contact departure is after takeoff, as mentioned in the next section:
b. After takeoff.
1. When the aircraft is about 1/2 mile beyond the runway end, instruct civil aircraft, and military transport, and cargo types to contact departure control, provided further communication with you is not required.
2. Do not request departing military turboprop/turbojet aircraft (except transport and cargo types) to make radio frequency or radar beacon changes before the aircraft reaches 2,500 feet above the surface.
That should give you some insight into things, at least how they run in the US.