The ground test program for SpaceShipOne, including rocket propulsion integration, has been active since the summer of 02. As of May 03, SpaceShipOne had completed most structural tests and systems qualification tests. Tests remaining to qualify the ship for glide testing are cabin pressure proof tests, some control system proof tests, additional landing gear functional tests and the GVT program. The following includes tests after mid May 03, updated periodically.

Date: 8 - 21 Oct 2003 Horizontal Tail Modification Aerodynamic Tests
       
Objectives:
SpaceShipOne, being the first manned winged aircraft with outboard horizontal tails, is a bit of a pioneer. The outboard tail operating in an upwash flow-field, is significantly more effective than a conventional tail. However, its span traverses the main wing’s tip vortex and thus sees a non-uniform angle of attack. Our CFD analysis was not complete enough to predict the tail’s airflow separation, which led to the nose rise departure during aft-cg stall testing (Flight # 37L / 06G). In response, Scaled conducted full-scale “wind tunnel” tests of the SS1 boom-tail using a modified Ford-250 pickup truck to provide the necessary flow field. A couple pictures of the test set-up is shown in the “photos” section. The purpose of these tests was to examine various changes to SpaceShipOne’s tail assembly to provide for better horizontal tail lift and tail lift-slope characteristics.

Results:
The testing conducted from 8 to 21 October successfully validated several aerodynamic fixes to solve the tail stall problem. The fixes were first flown on Flight 38L / 07G.

Date: 14-24 July 2003 System Tests
       
Objectives:
System level qualification tests for several subsystems

Results:
Completed landing gear qualification tests, brake tests and low speed taxi tests. Required changing the nose skid material to prevent excessive wear. Finalized cabin proof pressure test and leak rate tests. Completed structural load tests of the horizontal stabilizer, flight control system and feather mechanism.

Date: 24 Jun - 09 Jul 03 System Tests
       
Objectives:
To ensure the as-built systems meet the vehicle design requirements

Results:
Landing gear functional tests completed. Flight control system and structural qualification tests completed. Flight test data calibrations completed.

Date: 21-23 May 03 Ground Vibration Testing (flutter qualification)
       
Objectives:
To update the stiffness and mass distributions of the SpaceShipOne structural model so the analytical predictions match the actual vehicle frequency and modal response to a series of different forced vibrations. Since most flutter issues are critical for the rocket-powered flight tests, a rocket motor CTN was installed in SpaceShipOne for the GVT shake testing. The motor was one that had been fired for 15 seconds so its remaining fuel mass best represented that for the max-q portion of the boost flight.

Results:
The entire ship was hung on springs for the tests. The shakes were completed on schedule. The flutter analysis is in-work.