• Abstract and Figures
• Public Full-text

AAIB Bulletin: 4/2008 CONTENTS SPECIAL BULLETINS None COMMERCIAL AIR TRANSPORT FIXED WING Beech B200 Super King Air G-BYCP 24-Mar-07 1 DHC-8-402 G-JECG 10-Dec-06 8 Embraer EMB-145EP G-RJXA 10-May-07 27 ROTORCRAFT Sikorsky S-92A G-CHCK 23-Apr-07 36 GENERAL AVIATION FIXED WING Bolkow F.207 D-EHUQ 05-Nov-07 46 Jodel DR1050 Ambassadeur G-BXYJ 16-Feb-08 47 Kolb Twinstar Mk 3 (Modified) G-BYTA 16-Nov-07 48 Piper PA-25-235 Pawnee G-ASVP 17-Jun-07 50 Piper PA-28-140 Cherokee G-ATMW 01-Nov-07 53 Slingsby T67M260 Firefly G-BYOB 03-Aug-07 57 ROTORCRAFT None SPORT AVIATION / BALLOONS Airborne Edge XT912-B/Streak III-B G-CEHH 28-Mar-07 64 Chaser S G-MVVU 28-Aug-07 68 Gemini Flash IIA G-MTIA 18-Apr-07 70 Ikarus C42 FB80 G-SJEN 17-Jul-07 72 Thruster T600N 450 G-REDZ 15-Jul-07 74 ADDENDA and CORRECTIONS None List of recent aircraft accident reports issued by the AAIB 75 (ALL TIMES IN THIS BULLETIN ARE UTC) © Crown copyrght 2008 AAIB Bulletin: 4/2008 © Crown copyrght 2008 AAIB Bulletin: 4/2008 G-BYCP EW/C2007/03/07 ACCIDENT Aircraft Type and Registration: Beech B200 Super Kng Ar, G-BYCP No & Type of Engines: 2 Pratt & Whtney PT6A-42 turboprop engnes Year of Manufacture: 98 Date & Time (UTC): 24 March 2007 at 635 hrs Location: Southend Arport, Essex Type of Flight: Commercal Ar Transport (Passenger) Persons on Board: Crew - 2 Passengers - 5 Injuries: Crew - None Passengers - None Nature of Damage: Damage to nose fuselage, the nose landng gear and doors, and propeller tps Commander’s Licence: Commercal Plot’s Lcence Commander’s Age: 44 years Commander’s Flying Experience: 3,800 hours (of whch 2,200 hrs were on type) Last 90 days - 37 hours Last 28 days - 30 hours Information Source: AAIB Feld Investgaton Synopsis After selectng the landng gear to UP after takeoff but only 532 cycles snce ts last ,000 cycle check. from Caen, the ‘gear unsafe’ lght remaned on. The flight crew established that the nose landing gear One Safety Recommendaton s made. had nether retracted nor remaned locked down and, History of the flight despte recyclng the gear and attemptng to use of the emergency gear lowerng system, the crew were The arcraft departed from Caen Arport n France for unable to lock the leg down. On landng at Southend a flight to Stapleford Aerodrome, Essex. On board Arport, the nose leg collapsed, causng damage to the were a flight crew of two and five passengers, three of fuselage nose structure and the propeller blade tps. whom were young chldren. When the landng gear The nvestgaton revealed that the nose gear actuator was retracted after takeoff, the crew heard an unusual had been affected nternally by corroson, resultng nose from the vcnty of the nose landng gear bay, and from water ngress, whch led to the falure of the notced that the red ‘gear unsafe’ lght n the landng gear threads wthn the actuaton nut of the actuator. It had handle remaned llumnated. The man gear was seen completed a total of ,449 cycles of ts 8,000 cycle lfe, to be up, wth all three green ‘gear down and locked’ © Crown copyrght 2008 AAIB Bulletin: 4/2008 G-BYCP EW/C2007/03/07 lghts extngushed, but the nose gear, whch was vsble had prevously dscussed, the commander nstructed the by reflection in the engine cowlings, was not. Instead, co-plot to feather the propellers and to shut down both t appeared to be extended, but at a slght angle from ts engnes. The commander kept the nose rased for as normal down poston. long as possble before, at an estmated speed of 65 kt, t lowered and made contact wth the runway. The crew selected the landng gear down, and obtaned two green lghts for the man gear, but no such ndcaton After comng to a halt, the commander secured the for the nose gear. They then selected t up agan, but the arcraft whlst the co-plot went back nto the cabn and nose gear remaned n ts prevous poston. opened the man door. The arcraft had come to a stop on the runway n a nose down atttude, restng on the Initially, the flight proceeded towards Stapleford while two man landng gear legs and the nose landng gear the flight crew discussed the situation and briefed the doors. Because of the arcraft’s nose low atttude, there passengers. They then decded to dvert to Southend was a drop of two and a half to three feet below the Arport, whch was the ste of the operator’s mantenance ntegral stars. The co-plot descended to the ground and organisation. They notified their company, contacted the adult passengers passed the chldren to hm before Southend ATC to alert them to the problem and ntated they and the commander also evacuated the arcraft. the dverson as planned. The emergency servces were on the scene soon after the arcraft came to rest. At a range of 0 to 5 nm from Southend, the crew Landing gear system description selected the landng gear down but, agan, the man landng gears ndcated down and locked but the ‘gear The trcycle landng gear s electrcally operated and unsafe’ ndcaton remaned llumnated. They then controlled by the landng gear extenson/retracton attempted to lower the nose gear usng the manual handle located on the rght sde of the nstrument panel. extenson system, but wthout success. When t became A 28V motor/gearbox unt, located forward of the man clear that the arcraft would need to land wth an unsafe spar, drves the man landng gear actuators va torque gear, ATC nstructed the crew to hold overhead Southend shafts. The nose landng gear actuator s drven va whle the external emergency servces were alerted; the duplex chans from a sprocket attached to the motor arport emergency servces had already been placed on gearbox. These chans rotate an nput shaft nto the standby. Whlst n the hold, the commander brefed the actuator whch, va a bevel gear, rotates a steel screw co-plot on the landng and evacuaton procedures. The nsde a lubrcated alumnum bronze alloy nut. The passengers were also brefed. movement of the screw through the nut extends and retracts the actuator, and n turn, the nose landng gear. The arcraft left the hold and was vectored for a Internal frcton n the actuator holds the nose landng Survellance Radar Approach to Runway 06. There was gear n the retracted poston and the over-centre acton a northerly surface wnd of 0 kt and broken cloud at of the drag brace on the nose landng gear assembly 600 ft, wth a vsblty of 5,000 m n haze; the crew provdes a postve mechancal downlock. An expanded became vsual at about 600 ft and 2 nm from the arport. vew of the nose landng gear actuator s shown n A normal man gear touchdown was made and, as they Fgure . © Crown copyrght 2008 2 AAIB Bulletin: 4/2008 G-BYCP EW/C2007/03/07 Actuator screw Alumnum housng Actuator nut Figure 1 Nose Landng Gear Actuator Assembly Landng gear poston ndcaton s provded by A separate, manually operated, chan-drven system ndvdual green GEAR DOWN annuncators. Two provdes emergency landng gear extenson. Operaton red ndcator lghts n the control handle llumnate of the emergency handle dsconnects the motor from whenever the gear s n transt or not locked; absence the system and locks the emergency drve system of the of handle llumnaton ndcates that the gear s up and gearbox. A ratchet handle, actvated by hand pumpng, locked, or down and locked f combned wth ‘three drves the chan, and thus the actuators, to lower the greens’. man and nose landng gears. The system s desgned to lower all three landng gears at the same tme. © Crown copyrght 2008 3 AAIB Bulletin: 4/2008 G-BYCP EW/C2007/03/07 Aircraft examination There was evdence of compacted grease between the threads of the steel actuator screw thread along ts The arcraft had been moved nto a hangar and was length, and a consderable amount of alumnum bronze supported on jacks when vewed by the AAIB. Damage debrs was found wthn ths grease. Close examnaton to the arcraft was lmted to the fuselage skn around of the screw showed that corroson pttng damage was the area of the nose, the nose landng gear doors, and present, and that ths was more extensve at the upper the propeller blade tps. The nose landng gear actuator, and lower ends of the screw, Fgure 3. Corroson was although stll connected, was free to move and would present on the apex, roots and flanks of the threads, not lock n any poston. There was evdence of a and also observed on the nternal surface of the gears contamnated lqud, wth the appearance of a mx of wthn the alumnum housng. grease and water, orgnatng from wthn the actuator. Actuator maintenance Actuator examination Prior to 2005, the manufacturer specified that the The actuator was dsassembled and the alumnum nose landng gear actuator had an overhaul lfe of bronze nut assembly sectoned, to allow ts nteror to be 7,500 cycles, or a calendar lfe of sx years, whchever examned. Ths revealed that the nternal threads of the occured soonest. In 2005, ths was changed to threaded nut (screw nsert) assembly had been strpped, ntroduce a calendar lfe ‘backstop’ of sx years and a Fgure 2.

Load more

  77

Copy Link