Glendalegoon,
Understand and agree, you started with full flaps and retracted them to something less. You were in flight and probably called for TOGA/Flapsxx pushing power to max while retracting flaps to decrease drag, waiting for positive rate then gear up....
A GIV isn't a c150 where you can pop it off the ground by adding flaps. If they had flap 10 selected, and we're going 165 kts, selecting 20 or something greater would not have helped as there wasn't enough time for flaps to move with the remaining runway left.
GIV Rejected Takeoff procedure:
06-02-20: Rejected Takeoff 1. General:
Because of the diversity of Gulfstream operators, the decision as to who may direct call for a rejected takeoff is left to the individual operators. Once the decision is made to reject a takeoff, proceed as follows:
2. Procedure:
(See Figure 3.)
A. Pilot Flying (PF):
(1) Retard power levers to idle and apply maximum braking.
(2) Deploy speed brakes.
(3) Use reverse thrust if desired.
CAUTION
IF DIRECTIONAL CONTROL BECOMES DIFFICULT WHILE IN REVERSE THRUST, REDUCE THRUST TO REVERSE IDLE (OR FORWARD IDLE THRUST, IF REQUIRED). REGAIN DIRECTIONAL CONTROL, AND REAPPLY REVERSE THRUSTAS NECESSARY.
B. Pilot Not Flying (PNF):
(1) Verify ground spoiler deployment. If not deployed, PNF confirms PF has manually deployed speed brakes.
(2) Monitor engine instruments.
(3) Apply slight forward pressure on the control column.
(4) Notify tower of rejected takeoff as soon as conditions permit.
(5) When clear of runway, perform appropriate Emergency, Abnormal or Normal checklist, to include evacuating the aircraft, if desired.
NOTE:
After a rejected takeoff, the cabin pressurization system may still be in the FLIGHT mode of operation. Select the LANDING mode to allow the aircraft to depressurize.
(6) Check brake temperatures.
The NTSB mention there was a comment about a control issue. In all my years of training with jammed controls, I never had a session where at V1 I had a jammed elevator.
Again from the GIV manual:
Manual reversion of the pitch flight control system is also possible by closing a normally open flight power shutoff valve. The flight power shutoff valve is a mechanically operated shutoff valve located between the Combined and Flight hydraulic system pressure sources and the elevator actuator (as well as the aileron, rudder and flight / ground spoiler actuator) pressure lines. The valve consists of two mechanically connected but hydraulically isolated sections. A controlex cable connects the valve to a FLIGHT POWER SHUT OFF handle located on the left aft side of the cockpit center pedestal. See Figure 8.
Moving the FLIGHT POWER SHUT OFF handle up from its stowed (horizontal) position to the vertical position mechanically closes the flight power shutoff valve. With the valve closed, operating pressure is removed from the actuator, allowing the piston to idle.
The resultant advantage of the flight power shutoff provision is the ability to bypass a malfunctioning actuator (such as would be the need in the unlikely event of an actuator jam) and manually fly the aircraft. Although control column effort and response time to inputs are increased while in manual reversion, the aircraft remains capable of positive and harmonious.
4-15-30: Immovable Flight Controls:
DO NOT Pull Flight Power Shutoff Handle unless coupled with single engine emergency Rudder Control (Yaw) 1
PULL Flight Power Shutoff Handle Aileron Control (Roll) 2
PULL Flight Power Shutoff Handle Elevator Control (Pitch) 3
NOTE: Use only lateral and longitudinal trim after pulling Flight Power Shutoff Handle. Disengage Yaw Damper. Return directional trim to the neutral position prior to restoring h ydraulic boost to Ȁight control. If control is not regained in manual mode, return hydraulic boost to Ȁight controls. If Yaw Damper disengages as result of pulling Flight Power Shutoff Handle, do not attempt to reengage it until hydraulic pressure has been restored to Flight Controls....
Something else was happened.... There will be a chain link of events that happened that the NTSB hopefully will find. We all agree it wasn't a weather issue, nor an dangerous and challenging airport issue. The decision to use flap 10 is usually as it's normally used in high/hot second segment climb limiting issues; it does require more runway that selecting flaps 20.