Hi, looked through my old notes, I have some take-off and landing data for the -9 but nothing for the cruise unfortunately. For -15 I have take-off/cruise/landing data.
We used to use the following average fuel burns for -15...
JNB-NLA flight time 01:57 fuel 5900kg
JNB-TNR 02:44 8200kg
JNB-BZV 03:43 10,600kg
BZV-COO 02:31 7,200kg
COO-OUA 01:10 3,600kg
and as rule-of-thumb...
First half hour - 2020
First hour - 3300
First hour and half - 4400
First two hours - 5800
First two and half hrs - 7100
Hope this helps....
JD