- Parabolic Arc
- November 29, 2023
SpaceShipTwo Powered Flight No. 4 Flight Transcript
Part 3.1 in a Series
Below is an excerpt from the cockpit recording of the SpaceShipTwo crash on Oct. 31, 2014. The transcript picks up about 1.5 minutes prior to the spacecraft’s release from WhiteKnightTwo. The Mojave Air and Space Port’s control tower has just given SpaceShipTwo clearance to land on Runway 30.
Descriptions of what is happening in the SpaceShipTwo cockpit and what pilot Pete Siebold and co-pilot Mike Alsbury are doing are in brackets  and italics.
All times are given in UTC. The accident occurred at 10:07 a.m. PDT.
SpaceShipTwo Flight Transcript
Powered Flight No. 4
Oct. 31, 2014
Alright, you’re clear to arm, uh, at pylon release, I’ll call for fire, and uh…call the pitch up, pitch down, trim, feather unlock one point four.
I’ll uh, I’ll try to keep a hack on that three-forty-five as well.
Alright, then after, uh, shutdown, roll boost, uh, while we have some speed, roll boost will come off. primary (R-C-S) is uh, comin’ on. set the, uh, attitudes…feather uh, up, at uh, apogee…reset trims for minus ten…you’re cleared to feather at, uh, apogee, if I haven’t called for it, and, uh, remind me on the uh trims, if I haven’t gotten to ’em.
Alright, the visibility’s goin’ down a little bit here…I still have lakebed, and uh…
L minus thirty.
((scat two-one, glide trims good)) Green for release.
Stick is forward.
[Places both hands on control stick and moves it to a forward position.]
[Quickly moves left hand toward lower center console, then quickly moves left hand up to the LAUNCH CONTROL ARM switch.]
Armed. Yellow light.
[Removes left hand from LAUNCH CONTROL ARM switch, an amber colored arm pushbutton light below switch is illuminated.]
[Pilot places head firmly against headrest and slightly readjusts his seated position. Remains with head positioned on headrest until vehicle breakup. Co-pilot’s head is slightly off headrest and moves toward instrument panel as he reaches for switches on panel. At no time during the boost portion does co-pilot’s head touch the headrest. There is slight noticeable vibration to the pilot’s helmet due to it being pushed against the structure of the seat and minimal vibration noticeable to the co-pilot’s helmet during boost portion of flight.]
[Moves his left hand onto ROCKET MOTOR ARM AND FIRE panel and makes an upward motion in vicinity of a switch.]
[Moves left hand near ROCKET MOTOR ARM AND FIRE panel.]
WK2 Co-PILOT 17:07:15.92
((five. four. three.)) Two. One. Release. Release. ((release.))
SS2 CREW MEMBER 17:07:19.01
SS2 COCKPIT 17:07:19.27
[There is a visible jolt to cockpit and occupants.]
[mechanical sound associated with the operation of the SS2/WK2 release mechanism.]
SS2 COCKPIT 17:07:20.00
[Shadow of WK2’s wing can be seen quickly crossing inside of cabin of SS2]
[moves left hand toward ROCKET MOTOR ARM switch.]
[Makes quick motions with his left hand near ROCKET MOTOR ARM and FIRE switches.]
[Relaxes forward pressure on stick.]
SS2 COCKPIT 17:07:22.73
[Both PFDs auto sequence to BOOST phase and graphically change.]
[strained voice] Good light.
[Makes contact with left hand on left side of the control stick. Fingers and thumb of left hand appear to be around left horn of control stick.]
[Uses both hands on stick to make minor lateral movements to make left and right roll corrections.]
[strained voice] Yeehaw.
[Begins moving left hand off of left horn of control stick. Begins left hand movement toward Feather Lock Handles.]
SS2 COCKPIT 17:07:26.83
[PFD speed display on both PFD auto switches from ADC to INS by displaying the KEAS gauge from a black to a greyish white background.]
[strained voice] Point eight.
[Places left hand on Feather Lock Handles.]
[Moves Feather Lock Handles slightly right out of lock detent.]
[LT and RT Feather Lock Handles appear wider than previously seen. Handles appear to slightly diverge.]
[Co-pilot appears to be leaning forward and into a downward unlocking motion with his left arm and shoulder.]
[Pilot’s left thumb rapidly moved from right to left and back again in the immediate vicinity of the trim hat switch on the flight controls. The movement appeared consistent with a possible quick left lateral trim input.]
[Left hand is briefly removed from Feather Lock Handles and LT and RT portions appear to converge.]
[Left hand has shifted grip to LT side of LT and RT Feather Lock Handles.]
[A slight right motion to move LT and RT Feather Lock Handles out of LOCK detents.]
[A downward motion of Feather Lock Handles begins, handles appear to be slightly twisted with LT Feather Lock handle lower than RT Feather Lock handle.]
[Feather Lock Handles are in mid transit.]
[Feather Lock Handles appear to have reached UNLOCK position.]
[Relaxes Left hand grip on Feather Lock Handles while still touching mechanism.]
SS2 COCKPIT 17:07:29.57
[FEATHER NOT LOCKED Light illuminates on backup panel.]
[Moves left hand off of Feather Lock Handles.]
SS2 COCKPIT 17:07:30.67
[There is a slight but noticeable right roll indicated on ADI on both PFDs.]
SS2 COCKPIT 17:07:30.97
[FEATHER OK TO LOCK Light extinguishes, FEATHER NOT LOCKED Light remains illuminated.]
SS2 COCKPIT 17:07:31.40
[Both pilots’ bodies appear to begin to be pushed downward into their seats.]
[strained voice] Pitch up.
[strained voice] Pitch up.
[Pilot’s left thumb rapidly moved to a position just above the trim hat switch on the flight controls and remains near the hat trim switch until the end of the recording. During this time, no forward, aft or lateral trim input movements were seen.]
SS2 COCKPIT 17:07:31.80
[Backup FEATHER POSITION INDICATOR Light appears to have moved slightly upward on scale. ADI begins showing a pitch up trend on both PFDs.]
[Co-pilot’s head appears to move noticeably forward.]
SS2 COCKPIT 17:07:32.03
[Right roll indication on ADI on both PFDs appears to become more level.]
SIEBOLD & ALSBURY 17:07:32.26
[Sound of grunting]
[Co-pilot’s head continues to move forward toward his lap. There is some movement of left hand off of left knee.]
[Pilot’s head begins to move off headrest and slightly forward.]
SS2 COCKPIT 17:07:32.47
[There is a noticeable vibration to the cockpit image.]
SS2 COCKPIT 17:07:32.80
[Both pilots’ torsos appear to be slumped forward with their harnesses restraining their bodies. pilots’ heads have been pushed forward toward control panel and almost into their laps.]
SS2 COCKPIT 17:07:32.80
[End of recording. End of Transcript]
- Part 1: SpaceShipTwo’s PF04: A High Risk Fight
- Part 2: SpaceShipTwo Pilots Faced Extremely High Work Loads
- Part 3: A Good Light, Then a Fatal Mistake
- Part 3.1: SpaceShipTwo Powered Flight No. 4 Flight Transcript
- Part 3.2: The Breakup of SpaceShipTwo Frame by Frame From the Tail Boom
- Part 4: Pete Siebold’s Harrowing Descent
- Part 4.1: SpaceShipTwo Emergency Response Timeline
- Part 5: Shock, Tears & Spin: The Aftermath of the SpaceShipTwo Crash