Weighing Gliders

Single seater Two seater
Glider BGA number
Date weighed
Competition No.
Reg. (G-XXXX)
Manufacturers Serial No


Max Winch Max Aerotow
Max Rough Air VNE
Max manoeuvre

Placard Data

Weak Link Colour
Inspector Name

Weight units used
Length units used
Max Weight (with water) Ww
Max Weight (dry) Wd
Max Weight non lifting components Wn
May this glider fly at the BGA concession non-aerobatic higher weight?
Forward C of G limit (aft of datum) Xfl
Aft C of G limit (aft of datum) Xal
Fus & TP weight Wnl
Max seat load
Max weight in baggage compartment
Pilot forward of datum Xfs
Wheel to datum: Xfs

Note: This should be negative if aft of datum

Distance Datum to tail wheel/skid Xrs
Weight on main wheel Wf
Weight on tail skid Wr

Equipment Instruments
Cushions ASIs
Batteries Altimeters
GPS Mechanical Varios
Loggers Electric Varios
Permanent Ballast Director
Radio Compasses
Transponder ELT


This programme is provided for the convenience of inspectors and as a "quick check".  It will only do the sums for you.  It will give the wrong answers if you enter wrong information!  If you are at all suspicious of the answers or if they are significantly different from previous weighings, without good reason, please check your data and get someone else to double check it.  The most difficult and critical thing to measure is the distance from the wheel to datum.  An inch error can give a 20 lb error in minimum pilot weight.

The author and others have used this programme for several years without problems but the BGGC  and the author accept no responsibility for the consequences of mistakes or errors (mine or yours) when using this programme.

If anyone has any comments or constructive suggestions for improvements please contact me at tim@macfadyenhome.freeserve.co.uk

Tim Macfadyen 6 Jan 2008


This program uses the BGA weighing method as documented in the BGA AMP and inspectors should follow this procedure carefully to obtain the correct measurements.

Please note carefully that this method (unlike the earlier BGA method) measures the tail support from the Datum.


  • If your pilot position is aft of datum then put a minus sign in front of the distance.
  • If the wheel is forward of datum put the distance in as positive, if aft negative
  • The tailwheel to Datum measure is always positive


The output placards from this programme can be copied into "word" or similar and then changed to suit individual gliders, e.g. adding information on tail tanks, nose weights, fin batteries etc.

Where several calculations are needed, for example for gliders with adjustable seat backs and thus different pilot positions, run the programme several times with the different information and then combine it in one placard.

Max weight of non-lifting components

For virtually all gliders (except vintage ones) the manufacturers quote a maximum weight of non-lifting components.  This is the weight of everything except the wings, (the fuselage, TP, pilot, parachute and all other fuselage contents).  It is therefore essential to weigh the fuselage and TP separately from the wings to find the empty fuselage (& TP) weight.  For the very few types where a max weight of non lifting components is not quoted by the manufacturer, enter the max AUW (dry) in the “max weight of non-lifting components” box and enter zero in the “fuselage & TP weight” box.


Just to be clear, you use this program at your own risk, no liability is accepted for the results.