Small transport has gear malfunction, must land gear partially extended.

Attributes
ACN	226181
Time
Date	199211
Day	Sat
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : iad
State Reference	VA
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : mco
Operator	general aviation : personal
Make Model Name	Small Transport, Low Wing, 2 Recip Eng
Flight Phase	cruise other descent : approach landing other
Route In Use	enroute : on vectors
Flight Plan	None
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : atp pilot : cfi
Experience	flight time last 90 days : 50 flight time total : 2600 flight time type : 300
ASRS Report	226181
Person 2
Affiliation	Other
Function	other personnel other
Qualification	other other : other
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	other flight crewa
Resolutory Action	flight crew : declared emergency none taken : unable
Consequence	other
Supplementary
Primary Problem	Aircraft

Narrative:

During local flight in the fdk area, I noticed that the gear up indicator on the small transport had gone out. I placed the gear lever in the up position. The light did not go on and the handle did not return to neutral position as normal. This was the first indication of a gear malfunction. I proceeded towards the fdk airport. This aircraft is equipped with an electric hydraulic backup pump. I then tried to extend the gear with the electric pump system. The gear did not come down. This so far would indicate a loss of hydraulic fluid. I then tried the hand pump. The resistance on the hand pump did not feel normal. It felt 'spongy'... Like air in the system? I went through the preceding steps a second time. The same results occurred. I had one last back-up system left to use... CO2. Then I contacted my office for any other opinions before using the CO2. A chase plane observed the undercarriage in the up position. Then I decided to use the CO2 and observed the nose gear starting to extend. It extended only halfway. No other gear were observed by the chase plane. The chase plane returned to fdk. I call the office to inform them that I was going to have to land the aircraft 'gear up.' I also asked them to call hgr and iad to determine the best place to land gear up. They advised me to land iad. I had my office send another aircraft to follow me to iad. I had him observe my undercarriage and report that the left gear was somewhat extended...the nose gear had retracted somewhat. I called iad and declared an emergency. They gave me priority landing on 1R. I carried 110 mph on 1/4 mi final at 1000 AGL. Throttles went to idle, propeller to feather, mixture-idle-cutoff. Turned all electrical off except master. I bumped the starters on both engines to make propellers horizontal, then master off. I landed the aircraft smoothly on the runway with no loss of control. The aircraft came to a stop and we evacuated the aircraft. At this time, I believe there must have been a hydraulic leak downstream of the shuttle. Valves that separate the hydraulic/CO2 systems. I believe the hydraulic leak was such that when I initially observed the up indicator out and put the gear handle in the up position, the remaining fluid necessary to pump the gear down was exhausted.

Original NASA ASRS Text

Title: SMT HAS GEAR MALFUNCTION, MUST LAND GEAR PARTIALLY EXTENDED.

Narrative: DURING LCL FLT IN THE FDK AREA, I NOTICED THAT THE GEAR UP INDICATOR ON THE SMT HAD GONE OUT. I PLACED THE GEAR LEVER IN THE UP POS. THE LIGHT DID NOT GO ON AND THE HANDLE DID NOT RETURN TO NEUTRAL POS AS NORMAL. THIS WAS THE FIRST INDICATION OF A GEAR MALFUNCTION. I PROCEEDED TOWARDS THE FDK ARPT. THIS ACFT IS EQUIPPED WITH AN ELECTRIC HYD BACKUP PUMP. I THEN TRIED TO EXTEND THE GEAR WITH THE ELECTRIC PUMP SYS. THE GEAR DID NOT COME DOWN. THIS SO FAR WOULD INDICATE A LOSS OF HYD FLUID. I THEN TRIED THE HAND PUMP. THE RESISTANCE ON THE HAND PUMP DID NOT FEEL NORMAL. IT FELT 'SPONGY'... LIKE AIR IN THE SYS? I WENT THROUGH THE PRECEDING STEPS A SECOND TIME. THE SAME RESULTS OCCURRED. I HAD ONE LAST BACK-UP SYS LEFT TO USE... CO2. THEN I CONTACTED MY OFFICE FOR ANY OTHER OPINIONS BEFORE USING THE CO2. A CHASE PLANE OBSERVED THE UNDERCARRIAGE IN THE UP POS. THEN I DECIDED TO USE THE CO2 AND OBSERVED THE NOSE GEAR STARTING TO EXTEND. IT EXTENDED ONLY HALFWAY. NO OTHER GEAR WERE OBSERVED BY THE CHASE PLANE. THE CHASE PLANE RETURNED TO FDK. I CALL THE OFFICE TO INFORM THEM THAT I WAS GOING TO HAVE TO LAND THE ACFT 'GEAR UP.' I ALSO ASKED THEM TO CALL HGR AND IAD TO DETERMINE THE BEST PLACE TO LAND GEAR UP. THEY ADVISED ME TO LAND IAD. I HAD MY OFFICE SEND ANOTHER ACFT TO FOLLOW ME TO IAD. I HAD HIM OBSERVE MY UNDERCARRIAGE AND RPT THAT THE L GEAR WAS SOMEWHAT EXTENDED...THE NOSE GEAR HAD RETRACTED SOMEWHAT. I CALLED IAD AND DECLARED AN EMER. THEY GAVE ME PRIORITY LNDG ON 1R. I CARRIED 110 MPH ON 1/4 MI FINAL AT 1000 AGL. THROTTLES WENT TO IDLE, PROP TO FEATHER, MIXTURE-IDLE-CUTOFF. TURNED ALL ELECTRICAL OFF EXCEPT MASTER. I BUMPED THE STARTERS ON BOTH ENGS TO MAKE PROPS HORIZONTAL, THEN MASTER OFF. I LANDED THE ACFT SMOOTHLY ON THE RWY WITH NO LOSS OF CTL. THE ACFT CAME TO A STOP AND WE EVACUATED THE ACFT. AT THIS TIME, I BELIEVE THERE MUST HAVE BEEN A HYD LEAK DOWNSTREAM OF THE SHUTTLE. VALVES THAT SEPARATE THE HYD/CO2 SYSTEMS. I BELIEVE THE HYD LEAK WAS SUCH THAT WHEN I INITIALLY OBSERVED THE UP INDICATOR OUT AND PUT THE GEAR HANDLE IN THE UP POS, THE REMAINING FLUID NECESSARY TO PUMP THE GEAR DOWN WAS EXHAUSTED.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.