|Title:||Landed short, Serious incident occurring January 20th, 1999 at Frankfurt/Main to a Boeing B747-400 (Recommended)|
|Micro summary:||This Boeing 747-400 touched down on the underrun area before the main runway, damaging the main tires and resulting in a go-around in diminishing visibility.|
|Event Time:||1999-01-20 at 1639 UTC|
|Publishing Agency:||Federal Bureau of Aircraft Accidents Investigation (BFU)|
|Site of event:||Landing, Frankfurt|
|Departure:||Indira Gandhi International Airport, Delhi, India|
|Airplane Type(s):||Boeing 747-400|
|Type of flight:||Revenue|
|Executive Summary:||A B747-400 arriving from Delhi, with 311 passengers and 25 crewmembers on board approached runway 25 L at Frankfurt Airport at approximately 16:35 UTC. The approach to runway 25 L was conducted with the intention to perform a manual landing under CAT I conditions. This intention resulted from the ATIS (Automatic Terminal Information Service) of 16:20 UTC which was copied by the crew before starting the approach. The Meteorological Aerodrome Report contained in this ATIS indicated a visibility of 2 500 m and few clouds in 300 ft.|
Frankfurt Approach Control vectored the aircraft to a 9 NM localizer intercept for runway 25 L. The glideslope was captured just before the outer marker (FR) at approximately 1 400 ft GND, because the average sinkrate of 1 200 ft/min from Fl 110 to 4 000 ft respective 3 000 ft was too low for the remaining distance to the glideslope. When reaching an altitude of 3 000 the autoflight system was switched off and the airplane flown manually.
Apparently the crew did not realise the rapid deterioration of the visibility during the approach caused by fog-banks drifting in from the southwest. The additional special met report at 16:35 UTC indicating a decrease in visibility between 800 m RVR and 400 m RVR did not come to the knowledge of the crew. The landing clearance was issued before passing the outer marker (FR) at 16:37 UTC including the current RVR-readings for runway 25 L - A 300 m, B 550 m, C 375 m - and the advice that still CAT I is in process.
During the intermediate approach the crew dealt with a minor hydraulic pump malfunction in the hydraulic system number 4.
At approximately 800 ft GND the flaps were set from 250 to 300, the aircraft deviated about 100 ft above the glideslope. The sinkrate increased up to 1 450 ft/min and the aircraft went below glideslope at 400 ft GND. According to the flight crew the approach lights were sighted at a height of 300 ft. Because of the high sinkrate the GPWS sounded 8 times „SINKRATE, SINKRATE, SINKKRATE...“ and shortly after 16:39 UTC the aircraft touched down unintentionally, approximately 1 000 m prior to the touchdown zone on the hard surface of the old runway in front of runway 25 L. The pilot-in-command immediately initiated a go-around.
Meanwhile the RVR decreased so that at 16:50 UTC CAT II and from 16:54 UTC CAT III was in force. The second landing was performed at 16:58 UTC on runway 25 R as an automatic landing under CAT III conditions. Some of the previously damaged main landing gear tires started to burn, but were quickly extinguished by the fire brigade standing by. The fire crew had already been alerted by the tower controller because of an explosion-like sound at the time of the go-around.
The ground contact about 1 000 m in front of the touchdown zone (coming short) was the consequence
of an unstabilized final approach which was not discontinued by initiating a go-around procedure in a
Contributing factors were:
- The glideslope interception from above.
- A hydraulic malfunction during the approach requiring to perform the referring checklist
- The rapid deterioration of the visibility
- The continuation of the manual approach although the flight crew was not qualified for CAT II/III
- Poor crew co-ordination and missing crew resource management
|Learning Keywords:||Operations - Airspace - GPWS|
|Operations - Runway Underrun|
|Operations - Unstabilized Approach|
|Systems - Brake/Tire/Wheel Well Fire|
|Systems - Landing Gear|
|Systems - Landing Gear - Tires|
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