Is there anything here so important it has to be done on the runway? Years ago I thought you lost style points if the spoilers remained up any longer than necessary and as long as I was at it, I went ahead and did half the checklist. One day I was doing that and looked up to see us turning onto a crossing runway without ATC clearance. We got yelled at a little and I realized that a lot worse could have happened with my attention diverted. Of course back then when in the right seat I was the "pilot not flying" so it was all on the guy in the left seat. Or so I told myself. Now, as the "pilot monitoring," I do just that. Not a single item gets done until we exit the runway.
Everything here is from the G450 Aircraft Flight Manual, with a few comments in blue.
[G450 AFM §2-06-10]
Some pilots go right to OFF if they are done for the day. I recommend you keep the thing in STANDBY until you are in the chocks. When in STANDBY the radar antenna is centered and 15° up. If you place it to off there is no power to the antenna and it could get jostled around. While I've never heard of a failure because the pilot went to OFF during taxi, why not err on the side of caution? It is an expensive piece of equipment after all.
If you need to keep the transponder on for an ASDE-X program, you should turn the TCAS off to prevent an airborne airplane with a TCAS prior to version 7.0 detecting you on the ground.
NOTE: Check with the pilot flying prior to cleanup. At idle power, simultaneous flap retraction, and spoiler stowing with moderate braking may cause momentary PTU and auxiliary hydraulic pump activation. Reset the auxiliary pump, if necessary.
In the G-V we've seen brake "jerkiness" as a result of moving the flaps and ground spoilers while braking.
NOTE: If APU AIR is selected ON after landing, select the L and R ENG BLEED AIR switches to OFF. This will prevent thermal transients on the APU or possible damage to the APU when the power levers are moved above idle.
There are two schools of thought in the G450 when it comes to this part of the checklist. If it isn't too hot outside, leaving the bleeds on the engines will reduce the chances of you opening the cabin door with a lot of pressure inside the cabin. But the sooner you get those engine bleed switches off, the better your chances are of not restarting the engines with them on.
NOTE: If landing required hard braking, ensure brake temperatures have peaked and are decreasing. Note peak temperature and time from synoptic page for use in determining turn-around time and brake cooling requirements. See Chapter 5: Approach and Landing Planning and Performance.
A normal brake application in the G450 will add about 200°C to your brakes, and it may take up to 30 minutes for that peak to be realized. The limit, of course, is 650°C, but you need to be concerned before that. See G450 Abnormal Procedures / Brake System Overheat for more on this.
Gulfstream G450 Airplane Flight Manual, Revision 35, April 18, 2013