Phil747 From United Kingdom, joined Jan 2005, 7 posts, RR: 0 Posted (4 years 11 months 1 week 1 day 7 hours ago) and read 801 times:
Flying back from MIA to LHR on 31 December on AA56 we were at flt level 35000 approx near Richmond VA, when the plane felt like it was hit by something and dropped suddenly. It was quite scary. A few minutes later the captain announced that a 747 had crossed our path at the same level and we had been hit by its wake ? He also said that Washington Center had not warned him of another aircraft at the same level in the vicinity. Can anyone tell me if this was a serious occurance? Does this count as a reportable near miss?
FinnWings From Finland, joined Oct 2003, 640 posts, RR: 3 Reply 1, posted (4 years 11 months 1 week 1 day 7 hours ago) and read 779 times:
It wasn't too serious as you were at cruise altitude, but if the same would have happened on final approach the situation would have been more critical.
It isn't so rare to hit wake turbulence at cruise altitude... I spoke with an airline pilot a little time ago and he told that he had hit wake turbulence 3 times during the last year and all those were above FL100.
This is again one very good reason to keep your seat belt ALWAYS fastened.
Flymia From United States, joined Jun 2001, 3858 posts, RR: 5 Reply 2, posted (4 years 11 months 1 week 1 day 3 hours ago) and read 712 times:
Yea wake happens often. Its most dangerous on takeoff and landing. Thats the reason if you ever listen to ATC you will here. Eagle flight 546 clear for take off 9R caution wake turbulance. But at cruise it is no big deal. Turbulance almost all the time never does much anything to the plane when at crusing. Planes can withstand alot more than people think. What might be bad turbulance to the average passenger is nothing for the airplane.
"It was just four of us on the flight deck, trying to do our job" (Captain Al Haynes)
Vzlet From United States, joined Mar 2004, 776 posts, RR: 0 Reply 3, posted (4 years 11 months 1 week 1 day 2 hours ago) and read 696 times:
"at cruise it is no big deal"
Turbulence can indeed be a major problem!
This from the 1998 FAA / NASA Aircraft Turbulence Accident Prevention workshop: "Turbulence has been identified by the FAA, NTSB, and airline sources as a leading cause of aviation injuries, which costs the major airlines at least $100 million per year. Although there have been advances in the state-of-the-art of observing and forecast systems, these advances have not enhanced the quality of turbulence products for the aviation community. Consequently the turbulence accident rate per flight mile has not decreased in the recent past, and the number of accidents is expected to increase in proportion to the projected growth in air traffic volume."
SlamClick From United States, joined Nov 2003, 9996 posts, RR: 79 Reply 4, posted (4 years 11 months 1 week 1 day 2 hours ago) and read 687 times:
Serious? Potentially, very much so. I'll come back to that.
Near miss? I doubt it. Both aircraft were apparently being worked by the same controller, I have no reason to believe that minimum separation was compromised. The wake turbulence, specifically the wingtip vortices persist for several minutes. That other airplane may easily have been forty or fifty miles away by the time you encountered his wake. Remember we are each doing about eight miles a minute up there.
Now, back to the serious question: There are a couple of things to consider here. One is our speed, if we are crossing the wake at a right angle we will only be in the area of the vortices for about two tenths of a second. If we were following the other traffic it would be wise to alter course to the left or right to get out of his wake.
Wingtip vortices tend to roll you inboard, as measured from the plane leaving the vortices. The flow is UP at each wingtip. This is more serious if you are following the same ground track as the rolling can easily overpower the ailerons and spoilers. In fact, I have been rolled upside down on final approach. (It was rather exciting.) I count myself lucky because I was spit out of it. An encounter at a high angle, as, at cruise, is different.
The main effect here is sudden up an down drafts that will produce a violent bump. While it is not likely to damage an airplane, it could conceivably cause an upset if you were flying at the extreme high, or low end of your speed envelope. More likely, it will just toss loose objects around the cabin. This includes passengers standing in the aisles.
Industry wide, I'd guess we break a major bone or two at least once a year, and kill a passenger without damaging the airplane once ever three or four years. This is mostly in clear-air turbulence but I would not be surprised to learn that wake encounter could also do it.
Never, ever stand if you can be strapped in!
Happiness is not seeing another trite Ste. Maarten photo all week long.
Corsair2 From United States, joined Jan 2001, 248 posts, RR: 0 Reply 6, posted (4 years 11 months 1 week 1 day 1 hour ago) and read 661 times:
I was on an MD-80 approaching O'Hare when over Lake Michigan the airplane suddenly rolled 60 degrees to the left followed by a similar roll back to the right. The pilot later announced it as a wake turbulence encounter from a passing aircraft. That was rather scary after flying so many times and never seeing this happen.
BTW, I had always wondered if the unexplained crash of a United B727 into Lake Michigan back in the 1960's was actually caused by wake turbulence. Wake turbulence was not well understood back then and all the crash evidence pointed to all systems on the airplane working properly. We may never know..
"We have clearance Clarence. Roger, Roger. What's our vector Victor?"
Buckfifty From Canada, joined Oct 2001, 1283 posts, RR: 30 Reply 7, posted (4 years 11 months 1 week 1 day ago) and read 652 times:
My friend's old instructor died when his Piper hit the wake turbulence from a A320 near Winnipeg. That was quite a while ago, and it highlights the dangers of wake turbulence acutely in my eyes. I've heard the stories of planes flipping upside down, uncontrollable wing drops (anything from a B1900 to a A319), and severe jolts big enough to cause airframe damage and passenger injuries.
On a personal note, the strongest wake turbulence I've ever encountered was flying into our own wake holding at Lambourne on descent for LHR. The coffee in my hand was not in my hand anymore after the short jolt, luckily the cabin was already prepared for landing in this instance. Otherwise, I'm sure it would have meant more than spilled coffee back there.
SlamClick From United States, joined Nov 2003, 9996 posts, RR: 79 Reply 8, posted (4 years 11 months 1 week 1 day ago) and read 657 times:
2H4 I was in a Cessna 404. It was at about 400 AGL on final to the 24s at LAX. I don't know if I ever even knew what plane was in front of me. Had I known that I was going to roll clear over, I'd have gone with it and done a full roll. As it was, I was putting in aileron against it and losing the battle. I spent a week or two (okay, the fat part of a second) upside down before it started responding.
From that day to this, if I have a choice I'll be a quarter dot or so high on the glideslope when following one of the types that produce a lot of vortex. Like so many other things, it is all about avoidance.
Happiness is not seeing another trite Ste. Maarten photo all week long.
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