Narrative:

After rotation, positive rate of climb, attempted to retract landing gear. Gear handle would not move. Utilized uplock override and gear retracted. However, unsafe gear handle light remained on. Told vny tower of problem and requested/received ok to enter the pattern. On downwind tower said gear appeared up. Attempt to recycle, but same situation occurred. Made low approach and tower said gear appeared up. Requested/received ok to go to approach control (socal) for IFR to VFR on top. Socal told us to proceed to 5000 ft, hold south of fim. In climb noticed aircraft would not pressurize, speed and aoa flags came on. Captain decided to discontinue flight to phl. Took off with maximum fuel and after 45 mins hold still 2500 pounds over landing weight. Asked socal for permission to dump 2000 pounds of fuel and for their preference as to what location to dump. Socal requested dump in hold at fim at 6500 ft. At 6500 ft in hold dumped 2000 pounds of fuel. Received IFR clearance to vny and landed without incident. No emergency declared, no priority requested. Maintenance had svced gear struts prior to this flight and stuck gear strut causing no release of squat switch determined as cause.

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Original NASA ASRS Text

Title: AN ISRAEL IAI-1125 DUMPED FUEL AND RETURNED TO THE FIELD DUE TO LNDG GEAR UNSAFE INDICATIONS AND AIR SENSING FAILURE.

Narrative: AFTER ROTATION, POSITIVE RATE OF CLB, ATTEMPTED TO RETRACT LNDG GEAR. GEAR HANDLE WOULD NOT MOVE. UTILIZED UPLOCK OVERRIDE AND GEAR RETRACTED. HOWEVER, UNSAFE GEAR HANDLE LIGHT REMAINED ON. TOLD VNY TWR OF PROB AND REQUESTED/RECEIVED OK TO ENTER THE PATTERN. ON DOWNWIND TWR SAID GEAR APPEARED UP. ATTEMPT TO RECYCLE, BUT SAME SIT OCCURRED. MADE LOW APCH AND TWR SAID GEAR APPEARED UP. REQUESTED/RECEIVED OK TO GO TO APCH CTL (SOCAL) FOR IFR TO VFR ON TOP. SOCAL TOLD US TO PROCEED TO 5000 FT, HOLD S OF FIM. IN CLB NOTICED ACFT WOULD NOT PRESSURIZE, SPD AND AOA FLAGS CAME ON. CAPT DECIDED TO DISCONTINUE FLT TO PHL. TOOK OFF WITH MAX FUEL AND AFTER 45 MINS HOLD STILL 2500 LBS OVER LNDG WT. ASKED SOCAL FOR PERMISSION TO DUMP 2000 LBS OF FUEL AND FOR THEIR PREFERENCE AS TO WHAT LOCATION TO DUMP. SOCAL REQUESTED DUMP IN HOLD AT FIM AT 6500 FT. AT 6500 FT IN HOLD DUMPED 2000 LBS OF FUEL. RECEIVED IFR CLRNC TO VNY AND LANDED WITHOUT INCIDENT. NO EMER DECLARED, NO PRIORITY REQUESTED. MAINT HAD SVCED GEAR STRUTS PRIOR TO THIS FLT AND STUCK GEAR STRUT CAUSING NO RELEASE OF SQUAT SWITCH DETERMINED AS CAUSE.

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.