What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
On 09/22/2016 at 1001 am, I received a call from Abraham Lincoln Capital airport, Springfield Illinois (spi) tower dave simmons that N762MS declared an emergency into spi airport, for the reason of electrical and navigation failures.
The aircraft was seven (7) hours into their flight, leaving from london england to rogers Arkansas. Problem occurred while changing altitude to get above turbulence and on decent from the altitude is when the flight deck the automatic direction finding (adf) /multi-function control display units (mcdu) started flashing.
At 1015, the aircraft arrive at the ramp of horizon fixed base operation (FBO). The aircraft and crew and passenger were held on board due to the flight originating in london england, and no customs at spi. At 1230 pm the customs official arrived from decatur Illinois and released the aircraft on or about 1245 pm.
Once the aircraft was release, I was then able to question the crew on the situation and confirmed they did declare the emergency. The reason for the emergency landing was due to system failure of the electrical power. Related systems were the automatic direction finding (adf) /angle of attack (AOA)/ total ambient temperature (tat)/pressurization/flight control warnings and generator power, the generator hertz power would fluctuate between 400-120HZ.
As the second in command would try to review and make corrections on the (synoptic page) eicas synoptic display system, it would then kick in another fault rejecting the correction. After several attempts the crews then decided to hand fly the aircraft into Abraham Lincoln Capital airport, Springfield Illinois (spi). The reasoning to fly into spi was for the length of the runway. With all of the fault/failure they were not sure they had brakes and with the 8200 foot runway they were sure they could stop the aircraft without incident. The crew went through a check of systems to confirm they were operational. Flight controls ? Confirmed they had control of the aircraft. Lowered the landing gear ? Confirmed the gear down and locked. Next system to check was once they landed steering capabilities. They called the tower and informed the tower they would come to a complete stop and check nose wheel steering. They verified and taxied to the gate without further incident. Gulfstream fast team due to arrive at 1600 hours on 09/22/2016 to check out the aircraft and return to base.
09/23/2016 0845AM, checked in with gulfstreams maintenance team lead privacy data omitted on the corrections that were made to the aircraft. What they found was a code leading to a bad power distribution box (pdb) the transformer - rectifier units (trus) maybe inoperative which provides power to both generators, aux tru, battery charger and causing the power from the main cabin to shutoff. The pdb was removed and replaced and will be sent to Gulfstream engineering to review cause of failure. Bus power control units (bpcu), swapped position to see if problem moved from left to right; problem did not transfer. Verified by using inspection mirror that cannon plug/connector were still engaged on the back of the electrical panel since the aircraft just came out of C4 check on 9/17/2016. Verified there was no issue with left/right generators.
Aircraft was returned to service on 09/23/2016 0900 hours.
As the FAA filed it
ON 09/22/2016 AT 1001 AM, I RECEIVED A CALL FROM ABRAHAM LINCOLN CAPITAL AIRPORT, SPRINGFIELD ILLINOIS (SPI) TOWER DAVE SIMMONS THAT N762MS DECLARED AN EMERGENCY INTO SPI AIRPORT, FOR THE REASON OF ELECTRICAL AND NAVIGATION FAILURES.
THE AIRCRAFT WAS SEVEN (7) HOURS INTO THEIR FLIGHT, LEAVING FROM LONDON ENGLAND TO ROGERS ARKANSAS. PROBLEM OCCURRED WHILE CHANGING ALTITUDE TO GET ABOVE TURBULENCE AND ON DECENT FROM THE ALTITUDE IS WHEN THE FLIGHT DECK THE AUTOMATIC DIRECTION FINDING (ADF) /MULTI-FUNCTION CONTROL DISPLAY UNITS (MCDU) STARTED FLASHING.
AT 1015, THE AIRCRAFT ARRIVE AT THE RAMP OF HORIZON FIXED BASE OPERATION (FBO). THE AIRCRAFT AND CREW AND PASSENGER WERE HELD ON BOARD DUE TO THE FLIGHT ORIGINATING IN LONDON ENGLAND, AND NO CUSTOMS AT SPI. AT 1230 PM THE CUSTOMS OFFICIAL ARRIVED FROM DECATUR ILLINOIS AND RELEASED THE AIRCRAFT ON OR ABOUT 1245 PM.
ONCE THE AIRCRAFT WAS RELEASE, I WAS THEN ABLE TO QUESTION THE CREW ON THE SITUATION AND CONFIRMED THEY DID DECLARE THE EMERGENCY. THE REASON FOR THE EMERGENCY LANDING WAS DUE TO SYSTEM FAILURE OF THE ELECTRICAL POWER. RELATED SYSTEMS WERE THE AUTOMATIC DIRECTION FINDING (ADF) /ANGLE OF ATTACK (AOA)/ TOTAL AMBIENT TEMPERATURE (TAT)/PRESSURIZATION/FLIGHT CONTROL WARNINGS AND GENERATOR POWER, THE GENERATOR HERTZ POWER WOULD FLUCTUATE BETWEEN 400-120HZ.
AS THE SECOND IN COMMAND WOULD TRY TO REVIEW AND MAKE CORRECTIONS ON THE (SYNOPTIC PAGE) EICAS SYNOPTIC DISPLAY SYSTEM, IT WOULD THEN KICK IN ANOTHER FAULT REJECTING THE CORRECTION. AFTER SEVERAL ATTEMPTS THE CREWS THEN DECIDED TO HAND FLY THE AIRCRAFT INTO ABRAHAM LINCOLN CAPITAL AIRPORT, SPRINGFIELD ILLINOIS (SPI). THE REASONING TO FLY INTO SPI WAS FOR THE LENGTH OF THE RUNWAY. WITH ALL OF THE FAULT/FAILURE THEY WERE NOT SURE THEY HAD BRAKES AND WITH THE 8200 FOOT RUNWAY THEY WERE SURE THEY COULD STOP THE AIRCRAFT WITHOUT INCIDENT. THE CREW WENT THROUGH A CHECK OF SYSTEMS TO CONFIRM THEY WERE OPERATIONAL. FLIGHT CONTROLS ? CONFIRMED THEY HAD CONTROL OF THE AIRCRAFT. LOWERED THE LANDING GEAR ? CONFIRMED THE GEAR DOWN AND LOCKED. NEXT SYSTEM TO CHECK WAS ONCE THEY LANDED STEERING CAPABILITIES. THEY CALLED THE TOWER AND INFORMED THE TOWER THEY WOULD COME TO A COMPLETE STOP AND CHECK NOSE WHEEL STEERING. THEY VERIFIED AND TAXIED TO THE GATE WITHOUT FURTHER INCIDENT. GULFSTREAM FAST TEAM DUE TO ARRIVE AT 1600 HOURS ON 09/22/2016 TO CHECK OUT THE AIRCRAFT AND RETURN TO BASE.
09/23/2016 0845AM, CHECKED IN WITH GULFSTREAMS MAINTENANCE TEAM LEAD ^PRIVACY DATA OMITTED^ ON THE CORRECTIONS THAT WERE MADE TO THE AIRCRAFT. WHAT THEY FOUND WAS A CODE LEADING TO A BAD POWER DISTRIBUTION BOX (PDB) THE TRANSFORMER - RECTIFIER UNITS (TRUS) MAYBE INOPERATIVE WHICH PROVIDES POWER TO BOTH GENERATORS, AUX TRU, BATTERY CHARGER AND CAUSING THE POWER FROM THE MAIN CABIN TO SHUTOFF. THE PDB WAS REMOVED AND REPLACED AND WILL BE SENT TO GULFSTREAM ENGINEERING TO REVIEW CAUSE OF FAILURE. BUS POWER CONTROL UNITS (BPCU), SWAPPED POSITION TO SEE IF PROBLEM MOVED FROM LEFT TO RIGHT; PROBLEM DID NOT TRANSFER. VERIFIED BY USING INSPECTION MIRROR THAT CANNON PLUG/CONNECTOR WERE STILL ENGAGED ON THE BACK OF THE ELECTRICAL PANEL SINCE THE AIRCRAFT JUST CAME OUT OF C4 CHECK ON 9/17/2016. VERIFIED THERE WAS NO ISSUE WITH LEFT/RIGHT GENERATORS.
AIRCRAFT WAS RETURNED TO SERVICE ON 09/23/2016 0900 HOURS.