Lately, we've noticed what sounds like a huge airplane engine being tested [for lack of a better description] VERY late at night, sometimes two or three times a night [last night, Sunday, it sounded at 11:30 PM and again at 1:45 AM; comes on, runs for a bit, then literally "shuts off"--not the same as a take-off sound at all]. If we were close to Tinker, it would be understandable; if it were the sound of planes taking off [which is totally different], it would be understandable...but we have no idea who or what is causing this noise so late at night. It also doesn't seem to be every night.

And, yes, I know we live close to the airport; the normal sounds of planes aren't a problem. I lived under the flight path for Tinker for 20 years, so "normal" plane sounds are nothing unusual or surprising or even of interest to me. But this noise is something new, VERY loud, and seems to happen only late at night.

Does anyone know what is going on? Some new facility or repair area? "Con Air" testing out their engines??? Have no idea, but it certainly does wake us up!

I've been hearing it as well. I'm not there early AM or at night so I don't know if the company I am at is doing engine run-ups at night or not. It sounded like a pair of old JT-8D's without hushkits. At night the sound will be more noticeable as ambient sound is lower and the sound remains closer to the ground, whereas in the daytime it moves upward.

One of Allegiant's MD-87's was having engine work done today before a flight check (They use JT-8D powerplants). We might have been doing some work last night with them.

We've heard it, too, west of the airport.

I've been hearing it as well. I'm not there early AM or at night so I don't know if the company I am at is doing engine run-ups at night or not. It sounded like a pair of old JT-8D's without hushkits. At night the sound will be more noticeable as ambient sound is lower and the sound remains closer to the ground, whereas in the daytime it moves upward.

One of Allegiant's MD-87's was having engine work done today before a flight check (They use JT-8D powerplants). We might have been doing some work last night with them.

Not exactly sure what a "JT-8D" would sound like---but whatever it was, it definitely did NOT have a "hushkit"!!! Thanks for the info, SkyWest.

I spent 3 years living close to Dobbins ARB in Marietta, GA. I would hear the same thing there after dark. I lived about 2 miles from the base and it sounded like the engines were in the next room. Extremely loud and went on way to long to be something taking off plus the sound never moved. It would happen about 3 times and then done for the night.

I live near SW104th & May...heard it loud & clear Sunday evening...and yes it sounds exactly like engine testing. There's an ARINC hangar on the east side of the airport, but I have no idea if they would do engine runs there.

Is this going to be known as the Oklahoma City Hum?

http://www.straightdope.com/columns/read/1297/whats-the-story-with-the-taos-hum


The New Mexico congressional delegation--you remember what a big help they were investigating the alien spacecraft at Roswell--decided to harness the vast resources of the federal government to find out what caused the hum. However, the Pentagon denied all, and tests by scientists at Sandia and Los Alamos national laboratories and at the University of New Mexico (your tax dollars at work!) failed to detect the hum's source. A survey of 7,000 Taos-area residents found that only 2 percent had heard it. You're thinking: you could probably find 2 percent who think they've got microchips implanted in their brains! Hmm. Hmmmmmmmmmmmmmm. Sorry, thought I heard something.

Anyway, UNM hearing researcher James Kelly tells me they've done enough investigation to know this is more than just wacky Taos residents eating funny mushrooms. For one thing, tests show all the hum hearers hear pretty much the same low-frequency tone, making it unlikely they're imagining it or suffering from ordinary tinnitus. Research continues. Sure, it's all in their heads. The question is, what's "it"?

Thunder was firing up his tinfoil hat

Thunder was firing up his tinfoil hat

Oh stop!!

Earlywine, my husband also heard it at probably the same time you did.

When maintenance is done on aircraft the engine runs are typically done on the graveyard shift. This crew has the least amount of employee's. When doing engine runs the crew can not work on the plane so you don't have a lot of people sitting around getting paid for doing nothing. It is more than likely AAR do engine runs on aircraft in for maintenance checks. This is my observation from 20 years in aviation and 15 years with in air carrier maintenance.

When maintenance is done on aircraft the engine runs are typically done on the graveyard shift. This crew has the least amount of employee's. When doing engine runs the crew can not work on the plane so you don't have a lot of people sitting around getting paid for doing nothing. It is more than likely AAR do engine runs on aircraft in for maintenance checks. This is my observation from 20 years in aviation and 15 years with in air carrier maintenance.

My husband was wondering if it was AAR.

Not exactly sure what a "JT-8D" would sound like---but whatever it was, it definitely did NOT have a "hushkit"!!! Thanks for the info, SkyWest.

I think the JT part stands for Jet assisted Takeoff but that's just a guess...

JT-8D is an engine model number. And yes it was AAR.

Maybe they were doing this.

HXLkT70LZHo

or this

0toUq9UHCSA

The PW JT-8Ds are an engine model developed for the MD 80s, the 727 and variants -100 and -200 of the 737, by Pratt and Whitney. The MD 80s use a more powerful variant of the JT 8D, the 217A/B/C and 219, depending on what variant of the MD 80 you are looking at. Originally though, it was developed for the DC 9 model, with less powerful variants that suited that aircraft. Some aviation people still refer to the MD 80 as the DC 9-80, because before Douglas and McDonnell merged, it was to be continued as the DC 9, just that it was switched to the "MD" post-merger.

I have heard that the "JT" part stands for "Jet Turbine" but that's just what I've heard, could be wrong.

The MD-80 is a DC-9-80 per the FAA.

very true SkyWest. :)

^Ahh yes.