|Quoting Brenintw (Reply 14):
The cowling is designed and built by Boeing. There is a pic on this site of an MH 777 having its engine replaced where you can see the cowling opened up on the wing.
G'day Brenintw / Bobbidooley
These two photos are of the T - 700 installation on an A330;
On the left hand photo, you can see the engine with two sections of cowling opened. The cowling that is opened the highest is called the fan cowl, as this cowling covers the fancase area. The cowling behind it is called the "C" / "D" duct or thrust reverser (TR). The "C" / "D" duct or thrust reverser (TR) actually forms part of the bypass air duct.
The right hand photo shows that the fan cowl and "C" duct stay with the strut on engine changes. The engine comes away with two sections of cowling. The aft section is what I believe RR
terms an Integrated Nozzle Assembly (INA). The forward section is the nose inlet cowling, which is usually unbolted and fitted onto the engine that will be installed. I think the INA is part of the engine
These two photos show the difference in the external cowlings of the T - 700 / A330 and T - 800 / B 777 installations;
I have never worked on a T - 800 / B777 combination, but I would assume that the installations are broadly similar. From the photos above, the only major difference that I can see in the external cowlings is that there is no INA on the T - 800
. The TR mechanisms may also be different. The T - 700 / A330 uses a hinged petal configuration, whilst the T - 800 / B777 looks like it uses a translating cowl / blocker door / cascade configuration.
These photos give a clearer look at what happens. The left hand photo shows the raw engine removed from the aircraft (CF6-50?).
The nose inlet cowl has already been removed from the engine. There are three sections of cowling left on the pylon, from front to back, they are the fan cowl, the "C" / "D" duct or thrust reverser (TR), and the turbine cowling. This installation is on a DC10, but it is also typical of the GE
and P&W installations on the B747 / B767. The right hand photo shows the CF6 strut installation on a B742
installation on the 747 was slightly different. On RR
RB211-524G2's and D4's the TR
was a structural part of the engine, and remained with each engine when it was removed from the aircraft. There was no hinged turbine cowls either.
On the D4, the TR
pretty much formed the aft end of the bypass duct. On the G2, the TR
was joined with the INA to give the smooth contours of the engine. This combined TR
/ INA cowling came away with the engine on removal. This can be seen with the photos below, the D4 installation is on the left, the G2 on the right.
When a G2 or D4 is removed from a 747, the fan cowls are removed manually beforehand, which takes about 10 minutes. Once the engine is removed, all that is left is the strut alone, with no cowlings hanging off it; as seen below.
Anyway, I am not too sure about this, but I think that the general rule is that anything that remains on the strut is Boeing's or Airbus' responsibility, whilst anything that comes away with the engine is RR
's, P&W's or GE
[Edited 2006-11-08 09:11:29]