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MSYtristar
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757 Wake Turbulence /In-N-Out Burger Crash (1993)

Sat Aug 25, 2007 12:35 am

My coworker was telling me stories yesterday of his experiences dealing with wake turbulence over the years, and so of course our talk evolved into discussing 757 wake turbulence, and the subsequent related disasters caused by it. One story in particular caught my attention...it was the first time I've heard of it:

"On December 15, 1993, In-N-Out's president, Rich Snyder, son of the founders, and four other passengers died in a plane crash on approach to John Wayne Airport in Santa Ana, California after opening store #93 in Fresno.[12] Snyder was aboard a charter plane. The charter aircraft followed in a Boeing 757 for landing, became caught in its wake turbulence, rolled into a deep descent and crashed near the intersection of California State Route 55 and Edinger Avenue. The crash investigation led to the FAA requirement for an adequate period between heavy aircraft and following light aircraft to allow wake turbulence to diminish. As a result of this crash Rich's brother, Guy, assumed the presidency."

That company seemed to have a streak of bad luck to say the least in the 90's,as Guy died in 1999 from an overdose.

I am drawing a blank here...what are some other incidents related to the 757 wake? I know back in the 90's that aircraft received a lot of press regarding it.

[Edited 2007-08-24 17:59:55]
 
PYP757
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RE: 757 Wake Turbulence /In-N-Out Burger Crash

Sat Aug 25, 2007 12:39 am

Quoting MSYtristar (Thread starter):
The crash investigation led to the FAA requirement for an adequate period between heavy aircraft and following light aircraft to allow wake turbulence to diminish

Why is 757 described as a "heavy" aircraft? Of course everything is relative, but I thought this terminology was used only for wide-bodies.
 
zrs70
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RE: 757 Wake Turbulence /In-N-Out Burger Crash

Sat Aug 25, 2007 12:42 am

Is it possible to change the thread title? I read it and thought that this just happened, as no date was associated with it!
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rfields5421
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RE: 757 Wake Turbulence /In-N-Out Burger Crash

Sat Aug 25, 2007 12:43 am

Several incidents but I think this was the only accident/crash with that as a significant contributing factor.

Thought the B757 does not meet the normal requirements to be identified as a "Heavy" by it's weight, in the US it is identified as a Heavy so that trailing pilots know of the possibility of increased wake turbulence..

Europe and most of the rest of the world does not identify the B757 as a Heavy, relying instead upon controller and trailing pilots to realize the wake issue may exist and increase separation.
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roseflyer
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RE: 757 Wake Turbulence /In-N-Out Burger Crash

Sat Aug 25, 2007 12:45 am

Quoting PYP757 (Reply 1):
Why is 757 described as a "heavy" aircraft? Of course everything is relative, but I thought this terminology was used only for wide-bodies.

It's based on gross weight, and under certain weights the 757 can be considered a heavy. The 757-300 usually carries the heavy designation.

757s are notorious for having very bad wake vortices and turbulence behind them. They are worse than larger airplanes.
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spacecadet
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RE: 757 Wake Turbulence /In-N-Out Burger Crash

Sat Aug 25, 2007 12:49 am

Quoting PYP757 (Reply 1):
Why is 757 described as a "heavy" aircraft? Of course everything is relative, but I thought this terminology was used only for wide-bodies.

IIRC it's used for 757-300's and one particular airline's 757-200's that are over the weight requirement, though I forget which airline that is.

"Heavy" refers to a specific weight (IIRC a specific MTOW), not girth or potential for wake turbulence.

Just to clarify, most 757-200's are not referred to as "heavy" by ATC. If you hear it in relation to a 757, it's a 757 that's over the weight limit.

Someone else can fill in the details, because I've forgotten at this point what the weight in question actually is or which 757-200's are over the limit.

[Edited 2007-08-24 17:50:40]
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KPDX
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RE: 757 Wake Turbulence /In-N-Out Burger Crash

Sat Aug 25, 2007 12:50 am

Yea, you should change the title, scared the shit outta me.
 
flyingcat
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RE: 757 Wake Turbulence /In-N-Out Burger Crash

Sat Aug 25, 2007 12:56 am

Quoting KPDX (Reply 6):

I thought something had happened at LAX. Sudenly I want a double double.
 
bond007
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RE: 757 Wake Turbulence /In-N-Out Burger Crash (1993)

Sat Aug 25, 2007 1:00 am

Lot's of discussion on 757s and weights.
Heavy Rating (by JETBLUEATASW Aug 17 2007 in Tech Ops)

Jimbo
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SansVGs
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RE: 757 Wake Turbulence /In-N-Out Burger Crash

Sat Aug 25, 2007 1:03 am

Quoting Spacecadet (Reply 5):

"Heavy" refers to a specific weight (IIRC a specific MTOW), not girth or wake turbulence.

Yes, however, the main reason for using the term "Heavy" in an ATC context is for special spacing requirements to avoid wake turbulence. So if the bird "quacks like a heavy...call it a heavy" This is an example of not letting overly literalistic definitions get in the way of safety or common sense.
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FlyHoss
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RE: 757 Wake Turbulence /In-N-Out Burger Crash (1993)

Sat Aug 25, 2007 1:10 am

Here's a link to a NTSB report from an accident in December 1992 at Billings, MT:

http://www.ntsb.gov/ntsb/brief.asp?ev_id=20001211X16242&key=1

A Citation was following a B757 into Billings; 8 fatalities.
A little bit louder now, a lil bit louder now...
 
OPNLguy
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RE: 757 Wake Turbulence /In-N-Out Burger Crash (1993)

Sat Aug 25, 2007 1:21 am

Quoting Spacecadet (Reply 5):
"Heavy" refers to a specific weight (IIRC a specific MTOW), not girth or potential for wake turbulence.

It was 300,000 lbs. MTOW for a long time, but was changed to 255,000 lbs. MTOW some years back.
ALL views, opinions expressed are mine ONLY and are NOT representative of those shared by Southwest Airlines Co.
 
andessmf
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RE: 757 Wake Turbulence /In-N-Out Burger Crash (1993)

Sat Aug 25, 2007 1:39 am

This was one of the reasons why the worries over the A380 wake turbulence. No one at the time of these 757 turbulence accidents had any clue that the 757 would cause such problems.
 
aerobalance
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RE: 757 Wake Turbulence /In-N-Out Burger Crash (1993)

Sat Aug 25, 2007 1:41 am

It was a tragic crash that Dec. evening, I was in a Sunrise Aviation C152 that evening on a pleasure flight out to CNO and back from SNA. I was 3 aircraft behind the fallen jet, just handed off to Tower and lined up for 19R over Anaheim Hills, moments later I saw a fireball at my one o'clock and was immediately handed back to SoCal approach which had me vector over to Mile Square park and do some 360's. A few minutes later I was directed to overfly the airport at midfield and enter the pattern for 19L. It was only after landing and talking to ground frequency did I find out what happened.

What's spooky about this is that I often underflew the wake of many 757's while bugging out of SNA, on an Orange departure(330 heading), while they were entering their downwind to base turns over central orange county - been bumped around a few time. Now I strictly watch where I am in relation to any 757, and ATC does a decent job of warning people.
"Sing a song, play guitar, make it snappy..."
 
cloudyapple
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RE: 757 Wake Turbulence /In-N-Out Burger Crash (1993)

Sat Aug 25, 2007 2:10 am

B752:
US - Heavy
UK - Upper Medium
RoW - Heavy if in front, Medium if behind
A310/A319/20/21/A332/3/A343/6/A388/B732/5/7/8/B742/S/4/B752/B763/B772/3/W/E145/J41/MD11/83/90
 
cloudyapple
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RE: 757 Wake Turbulence /In-N-Out Burger Crash (19

Sat Aug 25, 2007 2:41 am

Quoting Spacecadet (Reply 5):
"Heavy" refers to a specific weight (IIRC a specific MTOW), not girth or potential for wake turbulence.

Back in the early days they thought the wake was directly proportional to the weight. Hence the use of the weight categories as the wake categories. This has been true for most aircraft types. Until the B752 came into service and blew a few lighties out of the sky that was.

Some studies ensued and somehow it was not recommended that the wake and weight categories to be delinked. So we still have the weight/wake categories and a few exceptions listed separately. It's a mish mesh what different countries are doing to accommodate the B752 but the general principle is to apply extra spacing to the following aircraft on final.
A310/A319/20/21/A332/3/A343/6/A388/B732/5/7/8/B742/S/4/B752/B763/B772/3/W/E145/J41/MD11/83/90
 
Faustino927
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RE: 757 Wake Turbulence /In-N-Out Burger Crash (1993)

Sat Aug 25, 2007 2:55 am

Quoting Zrs70 (Reply 2):
Is it possible to change the thread title? I read it and thought that this just happened, as no date was associated with it!

It clearly says 1993. Hello!!
Obsessed is just a word the lazy use to describe the dedicated.
 
MSYtristar
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RE: 757 Wake Turbulence /In-N-Out Burger Crash (1993)

Sat Aug 25, 2007 3:07 am

Quoting Faustino927 (Reply 16):
It clearly says 1993. Hello!!

Well, when I initially posted it, I didn't have 1993 in the title line.
 
etops1
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RE: 757 Wake Turbulence /In-N-Out Burger Crash (1993)

Sat Aug 25, 2007 3:07 am

usairways uses the "heavy " designator on their etops 757's. and so does ATA on both their 200's and 300's
 
cbphoto
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RE: 757 Wake Turbulence /In-N-Out Burger Crash (1993)

Sat Aug 25, 2007 3:11 am

Actually 757-200s are commonly referred to as heavy when a smaller aircraft is entrail of a 757 on approach. The Heavy designation that are used for the 255,000 MGTW use the "heavy" in their call sign. ATC often will let a smaller aircraft behind a 757 know that they are following a "heavy" 757 in regards to the wake turbulence that is produced behind it. This is what I observed and found out whiles working at the MSP tower. Now, unless the MSP tower does different practices then the rest of the country, that seems to be what they mean by a "heavy" 757. So if you hear tower call "Northwest 110 Heavy" you know its a 757-300. but if you hear tower say "N12345 your following a heavy 757" it does not necessarily mean they are following a 757-300!!"
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wagz
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RE: 757 Wake Turbulence /In-N-Out Burger Crash (1993)

Sat Aug 25, 2007 3:51 am

Quoting Etops1 (Reply 18):
usairways uses the "heavy " designator on their etops 757's. and so does ATA on both their 200's and 300's

I believe US has just instituted a new policy for filing as a "Heavy" regarding their 757s. I heard a Pilot/ATC conversation at PHL (also confirmed by a friend who works for US at PHL) that weight limits are 250,000 lb MTOW for domestic flights, and 300,000 lb MTOW for International. I didn't think the airline got to decide on that matter, but sure enough none of the ETOPS 757s from Europe that day used the Heavy appendix on the callsign.

For the record, this was last week. I assume it to be a recent change as well, since the controller seemed confused as to why aircraft he was used to seeing were no longer filed as "Heavy".
I think Big Foot is blurry... It's not the photographer's fault. There's a large out of focus monster roaming the countryside.
 
bond007
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RE: 757 Wake Turbulence /In-N-Out Burger Crash (1993)

Sat Aug 25, 2007 3:57 am

Quoting FlyHoss (Reply 10):
A Citation was following a B757 into Billings; 8 fatalities.

Yes, but had nothing to do specifically with the 757 or regulations... simply because he was flying too close. One of the last comments by the pilot was "..almost ran over a 757".

Quoting Aerobalance (Reply 13):
Now I strictly watch where I am in relation to any 757, and ATC does a decent job of warning people.

Well, in a C152, I'm not getting as close as 4 OR 5 miles behind a 757 or a 737, or a 717... regardless of whether it's 'heavy' or not  Wink


Jimbo
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soon7x7
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RE: 757 Wake Turbulence /In-N-Out Burger Crash (1993)

Sat Aug 25, 2007 3:57 am

The aircraft weight is not as culpable as the sweep of the wing. Heavy aircraft with shallow wing sweep create more redical vortices than do more streamlined sweeps.This is a negative by product of a high lift wing design.
 
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Acey559
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RE: 757 Wake Turbulence /In-N-Out Burger Crash (1993)

Sat Aug 25, 2007 4:01 am

One of my professors at school used to fly Beech 1900s for Skyway. She was coming into CLE following a 757 in IMC. The controller was in training and had everyone stacked perfectly 2 miles in trail, but didn't know or forgot about the added separation for 757s. Just as she popped out of the clouds she got stuck in the wake and the 1900 was rolled 120 degrees with a full load of pax. She said she's never been so scared in her entire flying career, and the outbound flight was delayed because they had to call a mechanic in to inspect the airframe, etc. Ironically enough, she ended up flying 757s for UA before being furloughed after 9/11.
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nema
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RE: 757 Wake Turbulence /In-N-Out Burger Crash (1993)

Sat Aug 25, 2007 5:19 am

Quoting Aerobalance (Reply 13):
I was 3 aircraft behind the fallen jet

Wow, that is extremely sad. Its bad enough to hear of any aviation disaster let alone being this close.
There isnt really a dark side to the moon, as a matter of fact its all dark!
 
FlyHoss
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RE: 757 Wake Turbulence /In-N-Out Burger Crash (1993)

Sat Aug 25, 2007 5:28 am

Quoting Bond007 (Reply 21):
Quoting FlyHoss (Reply 10):
A Citation was following a B757 into Billings; 8 fatalities.

Yes, but had nothing to do specifically with the 757 or regulations... simply because he was flying too close. One of the last comments by the pilot was "..almost ran over a 757".

Did they encounter wake turbulence from the 757 as a result of "flying too close?"

My point in posting the link to the BIllings accident was that it was just a year before the accident near SNA. As a result of these accidents, the 757 and the separation of aircraft following behind it received increased scrutiny.
A little bit louder now, a lil bit louder now...
 
UN_B732
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RE: 757 Wake Turbulence /In-N-Out Burger Crash (1993)

Sat Aug 25, 2007 5:30 am

I'm not sure if this is right, but I was talking to a Continental pilot, and he said they could takeoff 1 minute after a normal aircraft, 1:30 after a 757, and 2 after a heavy.
-A
What now?
 
aviateur
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RE: 757 Wake Turbulence /In-N-Out Burger Crash (1993)

Sat Aug 25, 2007 5:31 am

I am type rated in the 757 and I can tell you it is not designated with a "heavy" suffix in U.S. airspace. However, I believe the -300 model is.

In a study some years back, the 757 was determined to have the most severe wake of any aircraft ever built, of any size, military or civilian. Pretty incredible.

I published an article on wake turbulence that includes a story of what happened to a commuter plane I was captaining one day when landing behind a 757 at Philadelphia International. The piece includes links to some stupendous photos of wake turbulence here at Airliners.

The article is free to access, though you might have to hit the "skip this ad" option...

Wake turbulence:
http://www.salon.com/tech/col/smith/2006/11/10/askthepilot208/

- PS
Patrick Smith is an airline pilot, air travel columnist and author
 
bond007
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RE: 757 Wake Turbulence /In-N-Out Burger Crash (1993)

Sat Aug 25, 2007 5:33 am

Quoting FlyHoss (Reply 25):
Did they encounter wake turbulence from the 757 as a result of "flying too close?"

Yes. That was the NTSB conclusion ...even though it may well have been before the new regs ... and my conclusion, albeit my opinion, is when a pilot says "we almost ran over a 757" ... it's fairly logical I believe, to assume he was too close!! Read the link and make up your own conclusion.

Jimbo
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okierj
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RE: 757 Wake Turbulence /In-N-Out Burger Crash (1993)

Sat Aug 25, 2007 7:05 am

Just joined today, always enjoy reading everyones posts. It's interesting to read what pilots and avaition lovers have to say. From a controllers standpoint, the B752, even though not a heavy, gets treated like one. Though there are some differences in the distance between this airplane and heavy's. However, even though it gets treated almost like a heavy, we never call it a heavy. Only the B753, or that's what we see on our strips and scope is a heavy and will be called one.
An example would be if we put a B753 behind a B752 we'd only need 4 miles, and if it were the other way around it would be 5. Again, love reading everyones post and happy I found this site.
 
highflier92660
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RE: 757 Wake Turbulence /In-N-Out Burger Crash (1993)

Sat Aug 25, 2007 7:42 am

I would love to see them test a 757 with blended winglets to see if there is any appreciable difference. The In-N-Out Burger Westwind was closing quickly to the United 757 that had slowed to near Vref + 10. He was in trail, below and to the right of the 757, a terrible place to be and one ripe to encounter wake turbulence. The end result was that he ended up in the Santa Ana Auto Mall.

Unless you have the skills of the late Lockheed test pilot "Fish" Salmon and can roll a Beech Bonanza 360 degrees to emerge from wake, it's better to be one dot high in following a heavy.
 
STJ
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RE: 757 Wake Turbulence /In-N-Out Burger Crash (1993)

Sat Aug 25, 2007 7:58 am

In MSP when I monitor the tower I only hear the 757-300's referred to as "heavy" and if someone is following a 757-200 on the approach I will hear them say "caution wake turbulence you are following a 757" but I have never heard a 200 referred to as a "heavy"
 
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Stitch
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RE: 757 Wake Turbulence /In-N-Out Burger Crash (19

Sat Aug 25, 2007 8:08 am

Quoting RFields5421 (Reply 3):
Thought the B757 does not meet the normal requirements to be identified as a "Heavy" by it's weight, in the US it is identified as a Heavy so that trailing pilots know of the possibility of increased wake turbulence..



Quoting Cbphoto (Reply 19):
Actually 757-200s are commonly referred to as heavy when a smaller aircraft is entrail of a 757 on approach.

No disrespect, but you are both incorrect. Please see below:

Quoting Spacecadet (Reply 5):
Just to clarify, most 757-200's are not referred to as "heavy" by ATC. If you hear it in relation to a 757, it's a 757 that's over the weight limit.



Quoting Aviateur (Reply 27):
I am type rated in the 757 and I can tell you it is not designated with a "heavy" suffix in U.S. airspace. However, I believe the -300 model is.



Quoting STJ (Reply 31):
In MSP when I monitor the tower I only hear the 757-300's referred to as "heavy" and if someone is following a 757-200 on the approach I will hear them say "caution wake turbulence you are following a 757" but I have never heard a 200 referred to as a "heavy"

Correct.

I've done enough flying on UA and listened to Channel 9 on approach that in almost all incidents, ATC warns trailing traffic "You're following a 757, Caution, wake turbulence.".
 
N1120A
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RE: 757 Wake Turbulence /In-N-Out Burger Crash (1993)

Sat Aug 25, 2007 9:17 am

Quoting PYP757 (Reply 1):

Why is 757 described as a "heavy" aircraft?

Only the -300 and the -200s rated to the maximum 255,000 pounds are

Quoting Spacecadet (Reply 5):
and one particular airline's 757-200's that are over the weight requirement,

It isn't one airline. It is all airlines with 255,000 pound 752s.

Quoting Cloudyapple (Reply 15):

Back in the early days they thought the wake was directly proportional to the weight. Hence the use of the weight categories as the wake categories. This has been true for most aircraft types.

From what I know, the DC-10 also produces a stronger wake than heavier aircraft.

Quoting Cbphoto (Reply 19):
Actually 757-200s are commonly referred to as heavy when a smaller aircraft is entrail of a 757 on approach

No they aren't. Other aircraft are commonly warned of a 757 ahead by "caution wake turbulence" but only if they meet the heavy requirements are they referred to as heavy.
Mangeons les French fries, mais surtout pratiquons avec fierte le French kiss
 
bond007
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RE: 757 Wake Turbulence /In-N-Out Burger Crash (1993)

Sat Aug 25, 2007 9:30 am

Quoting N1120A (Reply 33):
No they aren't. Other aircraft are commonly warned of a 757 ahead by "caution wake turbulence" but only if they meet the heavy requirements are they referred to as heavy.

Just so we don't argue this  Wink

From the source ...7110.65

1. “Runway two seven left cleared to land, caution wake
turbulence, heavy Boeing 747 departing runway two seven
right.”
2. “Number two follow Boeing 757 on two-mile final.
Caution wake turbulence.”


Jimbo
I'd rather be on the ground wishing I was in the air, than in the air wishing I was on the ground!
 
deltajet757
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RE: 757 Wake Turbulence /In-N-Out Burger Crash (1993)

Sat Aug 25, 2007 10:44 am

Quoting Cbphoto (Reply 19):
Actually 757-200s are commonly referred to as heavy when a smaller aircraft is entrail of a 757 on approach.

Whenever I'm listening to the Sea-Tac ATC live feed on iTunes the controllers often say something, something, something...757 heavy...caution wake turbulence etc. That's what led me to think the 757 is a heavy in some respects but really it's about weight and some other stuff.

-DeltaJet757
FLY DELTA JETS
 
747400sp
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RE: 757 Wake Turbulence /In-N-Out Burger Crash (1993)

Sat Aug 25, 2007 11:50 am

I remeber that crash, I did not know that the president of In-N-Out Burgers was on that plane. I remeber Califorain 9 news ( now K-CAL 9), saying after the crash, that a 757 could put out more wake that a military transport.
 
Fly2HMO
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RE: 757 Wake Turbulence /In-N-Out Burger Crash (1993)

Sat Aug 25, 2007 11:54 am

Quoting RoseFlyer (Reply 4):
757s are notorious for having very bad wake vortices and turbulence behind them. They are worse than larger airplanes

Sorry, gonna have to be a smartass for once...

Source?

 angel 
 
peh
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RE: 757 Wake Turbulence /In-N-Out Burger Crash (1993)

Sat Aug 25, 2007 2:16 pm

Quoting Aviateur (Reply 27):
The article is free to access, though you might have to hit the "skip this ad" option...

Great article. Thanks for sharing.
Flown: ATR72, DASH 8, 737, 747, 767, 777, A300, A320, A321, A330, A340, MD80
 
tdscanuck
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RE: 757 Wake Turbulence /In-N-Out Burger Crash (1993)

Sat Aug 25, 2007 10:12 pm

Quoting Aviateur (Reply 27):

In a study some years back, the 757 was determined to have the most severe wake of any aircraft ever built, of any size, military or civilian. Pretty incredible.

That shouldn't be physically possible. Heaviest for its size I would accept, but it can't be more severe than a 747 or A380 or else you'd have a larger separation distance behind a 757 than you would behind the jumbos.

Quoting Highflier92660 (Reply 30):
I would love to see them test a 757 with blended winglets to see if there is any appreciable difference.

It's probably not noticeable under anything other than very controlled conditions. The wake has to be a little less intense or there'd be no advantage to the winglets, but it should be on the order of the drag reduction you get from the winglets (2-5%).

Tom.
 
OldAeroGuy
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RE: 757 Wake Turbulence /In-N-Out Burger Crash (1993)

Sat Aug 25, 2007 11:51 pm

Quoting Soon7x7 (Reply 22):
The aircraft weight is not as culpable as the sweep of the wing. Heavy aircraft with shallow wing sweep create more redical vortices than do more streamlined sweeps.This is a negative by product of a high lift wing design.

Wing sweep has very little impact on vortex strength. The primary factors are airplane weight, wing span, and speed. Vortex strength rises as weight increases and speed decreases. Increased span will reduce vortex strength.
Airplane design is easy, the difficulty is getting them to fly - Barnes Wallis
 
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Stitch
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RE: 757 Wake Turbulence /In-N-Out Burger Crash (1993)

Sun Aug 26, 2007 12:06 am

Quoting DeltaJet757 (Reply 35):
Whenever I'm listening to the Sea-Tac ATC live feed on iTunes the controllers often say something, something, something...757 heavy...caution wake turbulence etc. That's what led me to think the 757 is a heavy in some respects but really it's about weight and some other stuff.

I believe NW does fly some 753s out of SEA, which would explain why they are heavies. But being based out of SEA myself, everytime I am on a UA 752 or am listening to ATC discuss a 752, the "heavy" is not used, but the craft is warned that a 757 has departed ahead of them or they are trailing one on approach and to be cautious for wake turbulence.
 
UPS757Pilot
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RE: 757 Wake Turbulence /In-N-Out Burger Crash (1993)

Sun Aug 26, 2007 12:27 pm

I fly 757-200s and 767-300ERs for UPS, and we are NEVER designated a Heavy with ATC with the 757s. ATC will often anounce to our following traffic that we are a 757 caution wake turbulence, but we do not append a Heavy suffix to our 757 callsigns. (MTOW has to be greater than 300,000 lbs for the Heavy designation).
 
bond007
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RE: 757 Wake Turbulence /In-N-Out Burger Crash (1993)

Sun Aug 26, 2007 12:45 pm

Quoting UPS757Pilot (Reply 42):
but we do not append a Heavy suffix to our 757 callsigns.

Because as discussed, 757-200s are not 'Heavy' as per weight limits.

Quoting UPS757Pilot (Reply 42):
(MTOW has to be greater than 300,000 lbs for the Heavy designation).

You're a few years out of date, it's 255,000 lbs


Jimbo
I'd rather be on the ground wishing I was in the air, than in the air wishing I was on the ground!
 
cloudyapple
Posts: 1261
Joined: Sun Jul 24, 2005 7:01 am

RE: 757 Wake Turbulence /In-N-Out Burger Crash (19

Sun Aug 26, 2007 2:17 pm

Quoting UPS757Pilot (Reply 42):
we do not append a Heavy suffix to our 757 callsigns

And outside of America no one appends any heavy suffix to anything. It's a difference from ICAO standard phraseology. The aircraft type is on our strips so is the wake category. It's unnecessary to reiterate it on R/T. We do it day in day out so we know the separations by heart. The extra suffix is just clogging up valuable R/T resource.
A310/A319/20/21/A332/3/A343/6/A388/B732/5/7/8/B742/S/4/B752/B763/B772/3/W/E145/J41/MD11/83/90
 
bond007
Posts: 4428
Joined: Mon Mar 14, 2005 2:07 am

RE: 757 Wake Turbulence /In-N-Out Burger Crash (1993)

Sun Aug 26, 2007 9:22 pm

Quoting Cloudyapple (Reply 44):
The aircraft type is on our strips so is the wake category. It's unnecessary to reiterate it on R/T. We do it day in day out so we know the separations by heart. The extra suffix is just clogging up valuable R/T resource.

I never did understand that!
Presumably it was so you could, as in this example, have a B752 'Heavy', and a B752 not 'Heavy' depending on MTOW, but since the aircraft type code has preset characteristics, why not just create a new aircraft type code, like B75H if they REALLY need it. 99.9% of the time, it is completely redundant data.


Jimbo
I'd rather be on the ground wishing I was in the air, than in the air wishing I was on the ground!
 
soon7x7
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RE: 757 Wake Turbulence /In-N-Out Burger Crash (1993)

Tue Aug 28, 2007 11:38 pm

Response...OldAeroGuy...Generally speaking you are correct...in the case of HEAVY transport aircraft all of what you say is true but the wing sweep on the 757 is a big factor in landing profile, not so much what is happening at the wingtips, but more the effect that the outboard edges of the flaps have on wake turbulence.The lack of triple slots on the 757 with it's heavy load and forward wing forces more air volume to pass laterally outboard creating a nasty vortex.I was once told that it is a virtual impossibilty to see vortices eminate from the tops of winglets...See it all the time...I conducted a nightime photo study in ATL adjacent to the approach lights ,in low level fog of vortices from different aircraft types, the 757 had double vortices emminating from the outboard flap edge,an inner core and an outer core, the vortex from the tip was tight and narrow, the flap vortex was very large on the outside, very tight inside the core,VERY SCARY LOOKING! the 757 was the biggest offender, the L-1011, was the second. The 727 had all kinds of vortices from all over but seemed to fly the cleanest. MD-80 was nasty as well.If I find the negs,I will post on A.net.The FAA was even interested in the work as it portrayed visually the results the various aircraft had over each other.
 
bond007
Posts: 4428
Joined: Mon Mar 14, 2005 2:07 am

RE: 757 Wake Turbulence /In-N-Out Burger Crash (1993)

Wed Aug 29, 2007 12:31 am

Quoting Soon7x7 (Reply 46):
the 757 was the biggest offender

What I understand though, is that the 757 vortices dissipate more quickly than aircraft of a similar size.


Jimbo
I'd rather be on the ground wishing I was in the air, than in the air wishing I was on the ground!
 
charlienorth
Posts: 1069
Joined: Sat Jun 10, 2006 6:24 am

RE: 757 Wake Turbulence /In-N-Out Burger Crash (1993)

Wed Aug 29, 2007 12:44 am

I was riding cockpit jumpseat on an ATR42 going into ORD,the captain warned us that it was going to get rough because they pit us too close behind a 757,at about "Taft" it felt like we hit a brick wall,we didn't roll but for a split second it appeared the airspeed indicators went to zero,the captain told the new-hire F.O. not to fight it and we came out fine,but it was quite interesting to have a front row seat to something like that.
Work hard fly right..don't understand it
 
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tjwgrr
Posts: 2499
Joined: Fri Mar 24, 2000 4:09 am

RE: 757 Wake Turbulence /In-N-Out Burger Crash (1993)

Wed Aug 29, 2007 12:59 am

For what it's worth... I've monitored a few ATA 752 flights that were designated heavy by ATC.
Direct KNOBS, maintain 2700' until established on the localizer, cleared ILS runway 26 left approach.

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