PPRuNe Forums

PPRuNe Forums (https://www.pprune.org/)
-   Tech Log (https://www.pprune.org/tech-log-15/)
-   -   Rushing noise on ground under aircraft on short final. (https://www.pprune.org/tech-log/620724-rushing-noise-ground-under-aircraft-short-final.html)

Jump Complete 20th Apr 2019 15:51

Rushing noise on ground under aircraft on short final.
 
Mrs JC and I in West Yorkshire on anniversary weekend. Having been visiting Otley, a favourite of ours, we’ve been walking on The Chevin. On return leg of walk, we were directly under (looking up, between the left engine and the wingtip) of a 737 on about 1 1/2 final (edit: for Leeds-Bradford runway 14.) As it touched down, (we could see the runway from our vantage point.) we heard a ‘whooshing’ noise just above us. The aircraft had long passed and it was different from the airflow noise from a glider or throttled-back light aircraft. I assume we were actually hearing the wake vortexes. Any thoughts on this? Am I correct?

ImbracableCrunk 20th Apr 2019 16:01

You are correct. The employee parking lot at my base is right under final and I often hear the rushing whip-crack while I'm waiting for my bus.

Jump Complete 20th Apr 2019 17:21


Originally Posted by ImbracableCrunk (Post 10452027)
You are correct. The employee parking lot at my base is right under final and I often hear the rushing whip-crack while I'm waiting for my bus.

Thanks. Having been around and flying aircraft for a long time, to actually experience something only previously experienced in text books (well, apart from a few wake turbulence encounters) was very interesting.

Vessbot 20th Apr 2019 17:56

Once I was in a park on short final, and in addition to hearing the wake, one of every few of them would come down low enough to rustle up the tops of the trees.

fantom 20th Apr 2019 18:41

Sorry; you are all wrong.

It is the wake behind the captain's wallet.

BirdmanBerry 20th Apr 2019 19:05

The Green Man at Heathrow is a great place to experience this assuming the right runway is in use.

eckhard 20th Apr 2019 19:14

Or Sootbörn / Vogt-Cordes-Damm at HAM for RW05. Used to cycle there in my youth and heard the vortices from the 727s.

Oscar Charlie 192 20th Apr 2019 20:17

I live about 12 miles from runway 23 at Manchester and, one day last Autumn an Emirates A380 went overhead at circa 3,000'. Several minutes later the trees started rustling and we felt a breeze, despite the previous flat calm. A (very) rough calculation of height vs time corresponded with wake turbulence decay.

tdracer 21st Apr 2019 00:32

We used to play Ultimate Frisbee at lunchtime on the ball fields outside the Everett Boeing Fitness Center. It's north of the main Boeing campus, almost directly below the approach flight path to the main Paine Field runway. We'd often hear the sound of the wake vortexes ripping through the nearby trees about a minute after a large aircraft passed by on it's way to land. At times they'd even affect the flight path of the Frisbee (although probably not as often as was claimed - 'not my fault my throw was incomplete - a vortex got it' :hmm:).

westhawk 21st Apr 2019 09:24

I was attending sim training at CAE/DFW and had time for a round of golf at the course just South of the airport. As a single, I was paired with 3 normal everyday non-aviation people who were also visiting from out of town. I really got a kick out of watching their reaction every time a jet flew right over us to land. First, how fascinated they were seeing airliners fly 300' right over their heads, but even more so when the vortices settled. They kept looking around wondering where that whooshing noise was coming from! After about the tenth time, I just had to let them in on it...

Centaurus 22nd Apr 2019 02:41


wondering where that whooshing noise was coming from!
We used to get a similar noise when flying Tiger Moths. Especially when gliding to land and you could hear the soft whistling noise caused by the airflow between the bracing wires between the upper and lower mainplanes. You knew you were gliding too slow for safety if the whistling of the air got quieter and the next sound was the clacking of the auto-slats as they banged against the leading edge of the top wing signifying you were about to stall.

Thread creep ceases

Smythe 23rd Apr 2019 00:10

many youtube videos with wake sounds for comparision...(wake crack at 45 seconds)


neilki 30th Apr 2019 00:43

Whip Cracking?
 
might just be me but I thought that was Crew Scheduling...

Been Accounting 30th Apr 2019 04:38

I xperienced this when a Gnat flew between the tower and hangar at Cranfield. ;)

i was told they were called ... Bernoullis

Seems appropriate.

Bullethead 30th Apr 2019 06:11

G'day Gents,

A view from inside the cockpit.

Often when following a B747 on an overwater approach, for example to RW34L at YSSY across Botany Bay, in still conditions you could clearly see the where the wingtip vortices had descended and left their mark on the water surface of the bay. The southern shore of Botany Bay is about 3nm from the touchdown point and the approach altitude there would be around 1000ft and often the vortex tracks would extend all the way from the landing threshold to the southern shore of the bay spreading outwards as distance from the touchdown point increased.

Cheers,
BH.

Groundloop 30th Apr 2019 08:30

Used to be really noticeable underneath a 757.


All times are GMT. The time now is 00:31.


Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.