|Quoting Laxintl (Reply 3):|
The key always was that the performance was always based on the lowest thrust version. So in other words, if one had a mix of JT9D-7A, 7J, 7Q's etc they would consider all operating to the -7A limits.
|Quoting USAFMXOfficer (Reply 6):|
Gotta love the intermix on the B-36...
|Quoting 9V-SVC (Thread starter):|
Can An Aircraft Use 2 Different Types Of Engines?
|Quoting Laxintl (Reply 8):|
The 747 Classic intermix is certainly something to keep the F/E busy, however is done routinely.
|Quoting Jetlagged (Reply 5):|
It's likely that auto-throttle use would be avoided on takeoff and climb (not a big disadvantage on a 747 Classic).
|Quoting Air2gxs (Reply 7):|
Agreed, but my concern is the EGT indication. If I remember correctly, it is substantially lower on the -7Q and may cause an issue during abnormal operations when the flight crew is operating from training and instinct (you know, emergencies). Also, isn't the -7J rated at a higher temperature due to design? We have indicators installed on our aircraft that will illuminate yellow and red lights when you have an impending excedence or excedence, respectively. Operating the -7J at its upper limits would cause the lights to illuminate without cause.
|Quoting Greasespot (Reply 16):|
You can also intermix a JT8D-7/ 7B or a 9A on a B727 or a -9 or a -17 on a B737. Best part is you do ot even have to tell the crew they are flying with intermix engines....
|Quoting Accidentally (Reply 14):|
The 727 /RE has those big honkin JT8D-217 (think MD80) on the outboards and I think a -17 in the middle.