OVERWEIGHT LANDING

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Editor : Copyright Ó Smartcockpit.com / Ludovic ANDRE version 02 Smartcockpit.com BOEING 737 BRIEFINGS Page 1 OVERWEIGHT LANDING GENERAL · The aircraft landing weight should not exceed the maximum structural or performance limited landing weight unless an emergency exists & has been declared or the QRH calls for an immediate landing. · Overweight landings may be safely accomplished by using normal landing procedures and techniques. There are no adverse handling characteristics associated with heavier than normal landing weights. Although overweight landings do not necessarily have to cause structural damage if a minimum rate of descent is achieved on landing, it is recommended to dump fuel when the normal dumping procedure can be followed correctly & all circumstances are favorable… · Analysis has determined that, when landing at high gross weights at speeds associated with nonnormal procedures requiring flaps set at 15 or less, maximum effort stops may exceed the brake energy limits. The gross weights where this condition can occur are well above maximum landing weight. For these non-normal landings, maximize use of the available runway for stopping. · Reduce the landing weight as much as possible to minimize stopping distance. Since the 737 does not have a fuel jettison system, weight should be reduced at the Captain's discretion by holding at low altitude with a high drag configuration (gear down) to achieve maximum fuel burnoff (up to 8,600 pounds, 3,900 kilograms per hour). Conditions permitting, consider to switch ON the APU to increase fuel burn-off. · Check Autobrake stopping distance (Ops Manual Vol.3) · Fly a normal profile & ensure that a higher than normal rate of descent does not develop. · Observe flap placard speeds during flap extension and on final approach. In the holding and approach patterns, maneuvers should be flown at the normal maneuver speeds. During flap extension, airspeed can be reduced by as much as 20 knots below normal maneuver speeds before extending to the next flap position. These lower speeds will result in larger margins to the flap placards, while still providing normal bank angle maneuvering capability, but will not allow for a 15 degree overshoot margin in all cases. · Use the longest available runway, and consider wind and slope effects. Where possible avoid landing in tailwinds, on runways with negative slope, or on runways with less than normal braking conditions. · Do not carry excess airspeed on final. This is especially important when landing during an engine inoperative or other non-normal condition. · At weights above the maximum landing weight, the final approach maximum wind correction may be limited by the flap placards and load relief system. · Do not hold the airplane off waiting for a smooth landing. Fly the airplane onto the runway at the normal touchdown point. If a long landing is likely to occur : GO-AROUND ! Editor : Copyright Ó Smartcockpit.com / Ludovic ANDRE version 02 Smartcockpit.com BOEING 737 BRIEFINGS Page 2 · The pitch attitude will be about 2 or 3° higher than for Flaps 30 & care must be taken not to flare too much and allow a float to develop. · After touchdown, immediately apply maximum reverse thrust using all of the available runway for stopping to minimize brake temperatures. · Do not attempt to make an early runway turnoff. · After an overweight landing, Company Maintenance staff must be advised & appropriate maintenance checks carried out before further flight. (see Maintenance Manual) · In view of the increased aircraft weight, special attention shall be paid to the following items & conditions, when considering an overweight landing : - pilot's physical condition : own limitation & fatigue - weather : IMC or VMC, temperature, crosswind, turbulence, etc. - runway : elevation, length, slope, obstructions (at both ends), width & surface condition. - Aircraft : numbers of engines operating, serviceability of systems, flaps, etc. OVERWEIGHT AUTOLAND POLICY · Boeing cannot recommend overweight autolands. Autopilots on Boeing airplanes are not certified for automatic landings above maximum landing weight. At higher than normal speeds and weights, the performance of these systems may not be satisfactory and has not been thoroughly tested. An automatic approach may be attempted, however the pilot should disconnect the autopilot prior to flare height and accomplish a manual landing. · In an emergency, should the pilot determine that an overweight autoland is the safest course of action, the approach and landing should be closely monitored by the pilot and the following factors considered. - Touchdown may be beyond the normal touchdown zone; allow for, additional landing distance. - Touchdown at higher than normal sink rates may result in exceeding structural limits. - Plan for a go-around or manual landing if autoland performance is unsatisfactory; automatic go-arounds can be initiated until just prior to touchdown, and can be continued even if the airplane touches down after initiation of the go-around.