CE-680 Captain reported the stabilizer became jammed after takeoff rotation. CAS messages indicated inoperative autopilot stabilizer trim and primary stabilizer trim failure. Flight crew attempted to use secondary trim but that also did not work; requiring both crew members to exert forward pressure on the control column and slow the aircraft to maintain control and divert to a suitable airport.

Narrative

The flight was originating from ZZZ airport to ZZZ1 airport at night with no passengers. I'm pilot in command (PIC) of the trip; pilot flying from the right seat while second in command (SIC) pilot monitoring from the left seat. As per the weight and balance and TOLD (Take-off & Landing Data) card; I set the trim to -2.7 degrees. We started our engines at about XA05. We used the company/FAA approved Normal checklists: Before Start; Engine Start; After Start; Taxi; and Takeoff Checklist. We held short of Runway XX then cleared for takeoff. The left seat pilot lined up on the runway; transferred control to me on the right. Both pilots performed a flight control check on the runway; before I commenced the takeoff. No CAS (Crew Alert System) message was displayed; and APU was off. Takeoff was about XA15.I (right seat) rotated; with the left seat pilot calling normal callouts. After rotation; I felt more downward force was needed than normal as airspeed was increasing. I told him that I needed a lot more forward pressure; and that I don't have control. The SIC came up on the controls with me; as we both used both of our hands to push the nose down. We received the following Amber CAS messages: AP STAB TRIM INOP and PRIMARY STAB TRIM FAIL and I [advised ATC]. The controller asked to state the situation and asked if we wanted to head back. I said; No; going to ZZZ2". We were cleared direct ZZZ2; then I asked for vectors. We were given heading of 360 degrees. The controller then asked what attitude we wanted. The left seat responded that we cannot control the airplane and was given any altitude. The SIC selected secondary trim; and tried to add forward trim but it did not move. I also tried; and again it did not move. I pulled out the aircraft's "Pilots' Checklist" referred to the Emergency/Abnormal Procedures and ran the appropriate checklists. AP STAB TRIM INOP checklist was completed then moved on to PRIMARY STAB TRIM FAIL. While running the checklist; I also assisted the SIC with the forward pressure on the control column. As per the checklist; it referred me to the Emergency/Abnormal procedures; Jammed Stabilizer Trim System checklist. I used the second bullet point per our situation "Jammed at -2.00 To -5.0 (Typical Low Speed Cruise/Approach Configuration)" Our trim setting was at -2.7 degrees and stayed at that trim setting the entre flight. As per the checklist; it asked for speed limitation of "140 KIAS Maximum". We slowed the plane down and this allowed us more control at slower airspeed and less forward pressure was needed. I asked for the landing runway at ZZZ2 and was given the weather. We flew the visual to Runway XY backed up with the RNAV-Y. I manually set up the V REF of 106 KIAS. We were switched to tower and were cleared to land Runway XY. The Abnormal/ Emergency Checklist was completed. The SIC still has both hands on the control while I had my right hand on the yoke and left hand on the throttles. We flew the final together and landed together. We stopped on the runway was asked by tower if we can taxi with our own power. I replied in the affirmative; and was instructed to taxi via Runway XY and left on taxiway 1 to the ramp. ARFF (Airport Rescue and Firefighting) followed us to the ramp. We parked; completed the After Landing and the Shutdown/APU Off Checklist. I met with the maintenance team that was waiting for us outside of the hangar and also spoke to the Fire Chief."