View Full Version : I need help with table 1503/4/6

February 12th, 2012, 15:52
could someone please tell me the mysteries of tables 1503, 1504, 1506?? how do they work?? I need to duplicate the thrust curve vs throttle of a lyulka al-31F and although i can easily get the plane to reach mach 2.3, getting it to fly at 190 knts is a real mess.. I know these tables are where i need to be, but i dont understand the ratio between the two curves in each table. If someone could instruct me on how to properly adjust these curves so that i get the correct response at the correct throttle setting, i would greatly appreciate it..

February 13th, 2012, 07:10
I can only explain it in German.


February 13th, 2012, 21:41
Hey Pam, you've got a PM....

February 24th, 2012, 08:43
Perhaps of some assistance is a jet thrust flow chart on Jerry Beckwiths mud pond site. These tables can be a bit tiresome as one must adjust the curves one at a time to get each Mach level in correct relation. Bernt recently went through all of this with the F15 so hopefully he had some good points. I am lucky that my projects are currently really slow or solidly sub sonic.

Good luck! T

February 25th, 2012, 14:07
Thanks tom..
Sorry it takes me so long to reply. I dont focus so well any more without my med. I'll head over to the mudpond now and download those.

March 23rd, 2012, 12:46

Hope you are getting this sorted out. In effect N2 generated the gas production to run the N2 in a two spool engine. There are low vrs high mach curves for the two curves. To complicate the matters "reheat" is used to achieve plus oe Mach operation. So drag values come in here, and then often depending on the planform, operation at slow speed brings in high AOA drag and perhaps gear and flap drag.

So definitly a bunch of multiple variables.

Good luck! Tom