727 Air Intake Question

[Airnerd]

At MCI on Tuesday I was frantically driving around near the cargo apron trying to find the rental car return (a difficult task with the terrible signage and detours all over the place) when I saw a B727 with an oddly flared number 2 engine air intake. It bulged just behind the opening not unlike the intake on the MD11. I have never noticed this on a B727 before and was wondering if anyone knew what that was all about.
Sorry - unfortunately I don't remember who the plane was operating for even though it did have a name on it - but I'm guessing it must have been cargo or charter. It's livery was predominantly white. Thanks in advance!

[Petertenthije]

That would be the hushkitted model. They have new engines that would not normally fit in the normal engine shaft. As such it has been enlarged. I believe it also requires more air to go through it, hence the larger opening.

http://www.jetphotos.net/viewphoto.php?id=99174

[Stefano Rota]

The same here.

The TAME 727's have STAGE 3 Hush kits. In spite the fact they are HUSHKITS they sound very strong. They wake me up at night!

[Foxtrop]

Re:

All 721s have that characteristic bulge behind the air intake. The air intake w/r to the 721's #2 engine was designed as an oval, and then the engine casing behind that is circular, which looks like a bulge.

All UPS 727s have a larger air intake itself and the first half of the engine casing is enlarged b/c UPS's 72s have Rolls-Royce Tays, which have a larger diameter.

[Airnerd]

http://www.boeing.com/assocproducts/aircompat/acaps/727sec2.pdf

The official diagrams from Boeing show that the statement, "...all 727-100s have the bulge" is not true.
I think the bulge comes with the RR engine replacement for Stage III requirements. Thanks!

[Airnerd]

Okay... I did a little more poking around and have learned that the plane I saw was a 727-100QF (also referred to as a 727-100RE). These 721s have had all three JTD engines replaced with RR Tays. This solution is one of several available approaches to meeting Stage 3 noise requirements (and can meet Stage 4 requirements with minor modifications) and is apparently only offered for the 727-100 series aircraft. It was probably a UPS aircraft I saw at MCI as they have modified a good number of their 727-100s in this way and I don't know if any other operators have. Here is a close up of the 'hump' I was referring to:

photo:http://sobering.terracom.net/eaa99/UPS-727/
Thanks for the replies.

[Foxtrop]

Re:

Okay, I may have misunderstood your question, but yeah, that's basically the jist of it.

UPS has re-engined all 72s in its fleet with the RRTays. I think they're the same type as the ones on the F-100. It's the only operator which has done so. There's a UPS 722 out at Will Rogers Airport in Oklahoma City which has the RRs as well.

Btw, interesting fact: Boeing was originally considering the RRTay as the engine for the 72, but then switched to the JT8D instead. I garontee, we would be seeing more 72s flying around today had that been the case, and just possibly, a different version of the 72 as well.

Happy Flying!