Matthew Montano <mmontano@xxxxxxxxx> wrote:
>That makes sense, (that's why I questioned how true it would be.)
>
>But, as you alluded to, what's the average delta between max-takeoff
>weight and max-landing weight?
>
>Do bigger jets usually have a much bigger spread than smaller jets?
>
>And of course, it's all tempered with how long the runway is. ;-)
Setting the Max take-off and Max Landing Weights is the aircraft designer's
prerogative. As everything in life, it is a compromise. Lower design weights
allow a lighter structure, but at the same time limit the usefulness of the
aircraft. The lowest Max Landing Weight that makes sense equals empty weight
plus max payload plus reserve fuel. The highest Max Landing Weight is equal to
Max Take off Weight.
The intended use of the aircraft is the major factor in setting the spread
between Take off and Landing Weights. For an aircraft intended almost
exclusively for long-range flights, the Max Landing Weight can be lowish without
severely limiting the usefulness of the aircraft. On the other extreme, an
aircraft intended for short-range flights usually needs a highish Max Landing
Weight to allow multi-hop or return flights without refuelling.
Some data points:
Boeing 747-400 MTOW 800000 lb, MLW 574000 lb (28% spread)
Boeing 737-700 MTOW 154500 lb, MLW 129200 lb (16% spread)
Fokker 100 MTOW 91500 lb, MLW 84500 lb (8% spread)
Dornier 328JET MTOW 34525 lb, MLW 31725 lb (8% spread)
Please note that all of the above aircraft types are available at a range of
design weights. The above values are just typical ones, but show the
general trend.
Kees de Lezenne Coulander
C.M. de Lezenne Coulander
Aircraft Development and Systems Engineering B.V.
Hoofddorp, the Netherlands