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JammedStab
25th Feb 2016, 09:53
Read a magazine article by a retired pilot who said that a shockwave from the Concorde hit his aircraft once. Sounded interesting. Has anyone else experienced a shockwave from another aircraft during their career?



"With deference to Belgian cosmologist Georges Lemaître, I have my own version of the Big Bang theory, and it states that big bangs occur in clusters of three. My basis for this is that I had three big bangs during my airline career, and I am grateful not to have had more.

My first occurred when our Lockheed L–1011 was halfway between Los Angeles and Honolulu on Track Delta in clear, glassy air. My first officer, flight engineer, and I were enjoying crew meals at FL350 while marveling at a magnificent subtropical sunset. Life doesn’t get much better, I recall thinking.

The tranquility was shattered by a truly loud bang. The airplane shook once, but hard, as if a cosmic fist had given it a body blow—but it was over almost as quickly as it had begun. My crew and I exchanged startled, quizzical glances, wondering what had happened. It was similar to flying through the wake of a crossing aircraft, but this, we agreed, was like no wake encounter that any of us had ever experienced. We checked cabin pressure and then the other gauges and systems. Everything was normal, as though nothing had happened. The only lingering effect was our elevated pulse rates. I quickly explained to our passengers over the PA that we had flown through the wake turbulence of another aircraft, even though I knew better. What else could I say—that we had entered the Twilight Zone?

Twenty minutes later, we made a routine position report on HF and reported what we had experienced earlier. The ARINC operator said nonchalantly, “Oh, you must’ve been hit by a supersonic shock wave. A British Airways Concorde passed over you about 20 minutes ago.” A warning about this would have been nice."

AC560
25th Feb 2016, 13:20
What, I wonder, was said Concorde doing between LAX and HNL?

Charter flight, though I think they all left out of Oakland not LA (somebody will be along to correct).

wiggy
25th Feb 2016, 14:19
Has anyone else experienced a shockwave from another aircraft during their career?

A few times in my military days, but as far as civilian career and Concorde encounters just the one: We (744) were heading westbound on an Atlantic Track, a Concorde coming the other way and broadcasting the fact on air to air - we were on an 180 X 0 with lots of delta h :ok: . We saw it go over the top and the shockwaves manifested themselves as a fairly quiet double "knock" ..TBH I'm not sure we'd have noticed if it hadn't been for the heads up on the R/T...we certainly did not get a "loud bang".

FWIW the most impressive thing I remember about the encounter is having a peek up with the weather radar (old habits die hard) and seeing a return the size of a barn door well outside 20 miles ...stating the obvious but those intakes sure as heck weren't designed with stealth in mind.

tdracer
25th Feb 2016, 16:50
Jammed didn't mention a time frame, but towards the end there were a number of "special" Concorde flights from the US west coast where they basically headed out over the Pacific, accelerated to Mach 2, then turned around and came back.
The mother of a good friend of mine managed to get on one out of Seattle.:ok:

eckhard
25th Feb 2016, 17:16
Has anyone else experienced a shockwave from another aircraft during their career?

Like Wiggy, I too was 'bounced' once by CCDE in a 744. We departed JFK eastbound early one morning (the return sector of the 'daylight maniac') and watched the BA2(?) boarding as we taxied out. Sometime between Boston and Halifax, we felt a similar 'double knock'. As the conditions were otherwise serene, we immediately suspected the white pointy thing. Sure enough, there she was, overtaking us and a good 10,000ft higher.

Interesting to note that we flew backwards through the shockwaves!

JammedStab
25th Feb 2016, 21:39
What, I wonder, was said Concorde doing between LAX and HNL?

Now you know.

GlobalNav
25th Feb 2016, 21:41
Originally Posted by Amadis of Gaul View Post
What, I wonder, was said Concorde doing between LAX and HNL?

More than Mach 1, for sure.

LeadSled
26th Feb 2016, 05:47
Folks,
In its latter days, Concorde was a regular visitor to Sydney (YSSY) on non-schedules services, both BA and AF. Because they were unscheduled, the anti-noise mob never noticed, and missed the opportunity to experience severe damage and distress from "supersonic noise", on approach and departure.
Interestingly, twice, BA aircraft arrived with a good chunk of rudder missing, a fatigue problem apparently cause by acoustics.
The Day Concorde Lost its Rudder 12 April 1989 (http://www.airwaysmuseum.com/Concorde%20lost%20rudder%2089.htm)
Tootle pip!!

megan
27th Feb 2016, 00:19
I just don't know that I buy the story is all... Round the world charter flight

Departed London - NY 04/01/89
Leg #2 New York, NY - Acapulco 04/01/89
Leg #3 Acapulco, Mexico - Oakland 04/03/89
Leg #4 Oakland, CA - Honolulu 04/03/89
Leg #5 Honolulu, HI - Papeete 04/05/89
Leg #6 Papeete - Christchurch 04/08/89
Leg #7 Christchurch, New Zealand - Sydney 04/12/89
Leg #8 Sydney, Australia - Perth 04/15/89
Leg #9 Perth, Australia - Colombo 04/15/89
Leg #10 Colombo, Sri Lanka - Mombasa 04/17/89
Leg #11 Mombasa, Kenya - Cape Town 04/20/89
Leg #12 Cape Town, South Africa - Monrovia 04/23/89
Leg #13 Monrovia, Liberia - London 04/23/89

After the Concorde left Christchurch a section of rudder was lost. There was a "thud" and resultant vibration as the aircraft was climbing through 43,000 feet and accelerating to Mach 2. Repairs were carried out in Sydney.

Acrosport II
27th Feb 2016, 01:15
I wonder how effective the damaged rudder would have been in case of engine failure.


I guess there would still have been more than enough rudder to cope with asymmetric at high speed. What about approach speed.


I assume they didn't realise part of the rudder was missing for the flight across the Tasman.


Shame they are not still flying!.

riff_raff
27th Feb 2016, 05:47
I'm not a pilot, but I have lived in coastal southern California for several decades where there is a significant amount of commercial air traffic (SNA, LAX, LGB). I recall several times hearing the windows rattle violently from a double sonic boom as the Space Shuttle passed over on its way to landing at Edwards AFB. Don't remember any reports of commercial aircraft in the area being seriously affected by the shock waves though.