Please look at the necessary requirements regarding nav fit-out, fire suppression etc before posting. Some of your remarks are unprofessional.
If you try to load the "Island Resv" you will probably find yourself overweight for FHSH and its short runway. If you consult your lap top, FPPM, FCOM in that order you are well placed to comment. If you haven't or can't then take care not to say anything foolish. Ju
Now, going on from there let us say that a landing weight of 57 tonnes applies, there are no defects everything is tickety boo.
Landing Distance (LFL*0.6) 3030 feet by my laptop
Landing Ground Roll 1670 feet ditto
Is that not average deceleration of 15.5 ft/sec/sec? You check it for me.
FAOR FHSH
TO FUEL 14300kg: Zero Wind ISA Conditions: FIELD AND WT LIMITED
Payload 11000kg pax and bags
Flt Time 280mins
Air Dist 2029 am [zero wind ISA remember]
RoC 1520fpm
RoD 1470fpm
Mach No 0.783 nominal
Nett AS 434kts
Nett GS 434kts
FUEL 14300kg
OEW 42200kg
ZFW 53200kg
TOW 67500kg
DIV/ISLD 1600 kg 2400 kg/hr 40.0 min 320.0nm
HOLD 1600 kg 2400 kg/hr 40.0 min
CONT 620 kg inc start and taxi
TOTRES 3820 kg so it cannot be Island Resv but a "re-dispatch"
LDG 57020kg
Now go back and check and you will see that at 60 tonnes all up you might have to go back to Windhoek!
I was going to add more but it would not fit this page. No matter. But you have to be diligent. You have to do your sums and if the answer does not pan out then what you are proposing is not operationally possible
I hope this has helped and is not too simplistic.
Thank you.