Successful 'ditch' | Page 2 | FerrariChat

Successful 'ditch'

Discussion in 'Aviation Chat' started by zygomatic, Jan 15, 2009.

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  1. Rifledriver

    Rifledriver Three Time F1 World Champ

    Apr 29, 2004
    37,288
    Cowboy Capitol of the World
    Full Name:
    Brian Crall
    #26 Rifledriver, Jan 18, 2009
    Last edited: Jan 18, 2009
    The time required to be sure there was not traffic or even birds on the runway was probably more that he had at his disposal.

    His experience and confindence gave him the ability to act, act when others might waste time considering options. That is why there are 150 some odd people alive today instead of a smoking hole in the ground and a large funeral.

    He only cleared the GWB by 900 feet. Seems like a lot but how many seconds of flight time was that? He needed to act and act now and he did. That kind of decision making requires many years of experience and a guy who is at one with the airplane. Good on him.

    And to think he will be kicked out of the cockpit in three years because of an arbitrary rule.
    That rule needs to be changed. We are throwing some of our best pilots out on the street.

    I don't know about you guys but I get great comfort in looking left as I board an airliner and seeing some guy with crows feet and grey hair with 4 stripes on his sleeve.

    I know a lot of 60+ pilots that I will fly anywhere, anytime in anything with.
     
  2. vinuneuro

    vinuneuro F1 Rookie

    May 6, 2007
    2,574
    Chicago
    Full Name:
    Vig
    I believe he's also a Certified Glider Pilot which had to have been instrumental in how things turned out. Perhaps this is training that'd be valuable for airlines' pilots to have for obvious reasons. I find it a bit disturbing that there isn't a ditch procedure in place at some airlines, like CRUSING pointed out about his.
     
  3. Bob Parks

    Bob Parks F1 Veteran
    Consultant

    Nov 29, 2003
    8,018
    Shoreline,Washington
    Full Name:
    Robert Parks
    I have to agree 1000% with Rifle Driver! I also have known too many grey beards who were turned out way too soon and could have served well and safely AND passed on invaluable experience in technique and decision making.

    As far as making a tight 180 in a powerless swept wing aircraft, the aerodynamics are a deadly mix on top of the lack of a clear runway ahead. The inside wing in a tight turn starts to develop much more lift than the outside wing which can go into a stall from extreme angle of attack and lack of flow over an already aerodynamically thinner section. The result can be a violent snap roll . Wings level and straight ahead are always nicer in a swept wing airplane. At most, a gentle turn and best glide speed is healthy and survivable, as illustrated recently.
     
  4. solofast

    solofast Formula 3

    Oct 8, 2007
    1,773
    Indianapolis
    You aren't ever going to stall any airplane in any reasonalbe turn if you have sufficent airspeed. What you need to remember is that you are going to trade altitude for turn angle and so do not let your airspeed degrade sufficiently so that you stall. Swept wing airplanes have more drag at higher angles of attack, so you are going to trade more altitude for a turn than in a straight wing, but turning around is often a good option.

    I recall seeing a study where they did a series of emergency turn around manuevers to simulate power loss on takeoff. What they found is that if you lost power on takeoff just a short distance after the end of the runway you should have sufficient altitude that you can turn around and put it back down on the same runway. They also found that a fairly tight turn actually saved more energy (altitude) than a wider more gentle turn. The point being that you covered less distance in the turn and therefore burned up less energy over time.

    I am pretty confident that in this situation Sully did absolutely the right thing, but remember that every situation is different and you need to make your decisions on what you know and see at the time. Since he was a good way beyond the end of the runway he wasn't in any position to go back around. He managed his energy properly and did it perfectly, down to the point of picking his landing point near boats so that a rescue would happen quickly.

    I had a very good friend who lost power on takeoff shortly past the end of a long runway. He told the tower he had lost power and they asked if he wanted to declare an emergency. He said no but asked if he could land on the taxiway that he had just crossed over. They approved it and he cranked it around and put it down and then the tower told him to go to ground on .7, Ground came up and told him to taxi to the ramp, to which he replied that he was gonna need a tow back to the ramp since he had just lost the engine!!!

    And as to the point of older pilots I am with you 100%, remember "there are no old, bold, pilots" If I see a gray beard when I look to the left getting on board I feel a lot safer too...
     
  5. Bob Parks

    Bob Parks F1 Veteran
    Consultant

    Nov 29, 2003
    8,018
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    Robert Parks
    Dats what I said. Plenty of altitude, keep the turn gentle, and keep the nose down to keep up the airspeed. It is the tight, low altitude, emergency things that kill...especially in the big stuff. In my 70 years of messing around with airplanes I have witnessed too many deadly turn around-to-get back-to-the-airport crashes. One just two years ago by a high time experienced pilot. When I was at Boeing we lost a 707 to loss of directional control and a slipping yaw that degenerated into a snap roll and the eventual loss of the airplane.
     
  6. Bob Parks

    Bob Parks F1 Veteran
    Consultant

    Nov 29, 2003
    8,018
    Shoreline,Washington
    Full Name:
    Robert Parks
    I lied about messing around with airplanes for 70 years. It has been for 77 years. I'm bad at math. I started hanging out at the old Washington airport ( where the Pentagon is now) with my mom in 1932. First flight in 1935. Addicted airport bum kid after that until the present.
     
  7. CRUSING

    CRUSING Karting

    Oct 31, 2002
    235
    Jupiter, FL
    The retirement age is now 65 for 121 carriers. Changed Dec of 07.

    "You aren't ever going to stall any airplane in any reasonalbe turn if you have sufficent airspeed."

    Not entirely true. Speed has nothing to do with stalling contrary to what most people think. A wing stalls when it exceeds its critical angle of attack usually about 17-18 degrees. Speed is only a factor in relation to the relative wind. A wing can stall at any airspeed.

    But like you said, the turn needs to be reasonable. Pilots trying to make it back to the airport by tightening up the turn kill themselves nearly every week. Trying to hold altitude and turn increases the load factor on the wing- you end up increasing the angle of attack to hold altitude and come closer to the critical angle.

    As far as ditching training at the airlines - there are classes on ditching just no simulator training. We do go through a double engine failure and restart. Its done at 30 thousand feet.
     
  8. Spasso

    Spasso F1 World Champ

    Feb 16, 2003
    14,656
    The fabulous PNW
    Full Name:
    Han Solo
    #33 Spasso, Jan 18, 2009
    Last edited: Jan 18, 2009
    NEW YORK — The flight data recorder of the US Airways jet that landed in the Hudson River shows both engines lost power simultaneously, investigators said Sunday.

    Information from the flight recorders on the doomed aircraft was released as investigators worked to remove its fuel. After that is completed, officials hope to move the damaged plane off the river by the end of the day.

    "Defueling is a pretty intricate operation, not without risk," Kitty Higgins of the National Transportation Safety Board said at an afternoon briefing on the investigation.

    The crippled plane, hoisted from the river late Saturday, remains on top of a barge moored to a seawall in Manhattan a few blocks from the World Trade Center site.

    Higgins said the recorders showed that Flight 1549 reached a maximum altitude of 3,200 feet before losing power simultaneously in both engines before its splash-landing Thursday afternoon.

    Higgins recounted excerpts from communications captured by the cockpit voice recorder beginning 90 seconds after takeoff, when the captain made a remark to the co-pilot about birds.

    One second later, she said, "the sound of thumps and a rapid decrease in engine sounds" could be heard.

    "The captain makes a radio call to (Air Traffic Control) calling Mayday, and reports that they hit birds, lost both engines and were returning to LaGuardia" Airport, she said.

    Higgins said the accounts on the cockpit voice recorder were consistent with interviews with the flight crew. She also praised the crew.

    "Miracles happen because a lot of everyday things happen for years and years and years," she said. "These people knew what they were supposed to do and they did it and as a result, nobody lost their life."

    Higgins also said ice floes in the Hudson were hampering the search for the left engine, which separated from the aircraft and sank to the bottom of the river.
     
  9. Spasso

    Spasso F1 World Champ

    Feb 16, 2003
    14,656
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    Han Solo
    NEW YORK (AP) - The pilot of a crippled US Airways jet liner made a split-second decision to put down in the Hudson River because trying to return to the airport after birds knocked out both engines could have led to a "catastrophic" crash in a populated neighborhood, he told investigators Saturday.

    Capt. Chesley B. "Sully" Sullenberger said that in the few minutes he had to decide where to set down the powerless plane Thursday afternoon, he felt it was "too low, too slow" and near too many buildings to go anywhere else, according to the National Transportation Safety Board account of his testimony.

    The pilot and his first officer provided their first account to NTSB investigators Saturday of what unfolded inside US Airways Flight 1549 in the moments after it slammed into a flock of birds and lost both engines.

    Co-pilot Jeff Skiles, who was flying the plane, saw the birds coming in perfect formation, and made note of it. Sullenberger looked up, and in an instant his windscreen was filled with big, dark-brown birds.

    "His instinct was to duck," said NTSB board member Kitty Higgins, recounting their interview. Then there was a thump, the smell of burning birds, and silence as both aircraft engines cut out.

    The account illustrated how quickly things deteriorated after the bump at 3,000 feet, and their fast realization that returning to LaGuardia or getting to another airport was impossible.

    With both engines out, flight attendants described complete silence in the cabin, "like being in a library," said Higgins. A smoky haze and the odor of burning metal or electronics filled the plane.

    The blow had come out of nowhere. The NTSB said radar data confirmed that the aircraft intersected a group of "primary targets," almost certainly birds, as the jet climbed over the Bronx. Those targets had not been on the radar screen of the air traffic controller who approved the departure, Higgins said.

    Authorities also released a frantic 911 call that captured the drama of the flight. A man from the Bronx called at 3:29 p.m. Thursday, three minutes after the plane took off.

    "Oh my God! It was a big plane. I heard a big boom just now. We looked up, and the plane came straight over us, and it was turning. Oh my God!" the caller told 911.

    At almost the same moment, the pilot told air-traffic controllers that he would probably "end up in the Hudson."

    Most bird strikes happen within five miles of an airport, lower than 1,000 feet, as planes are taking off or landing. Aircraft hit thousands of birds every year, but they usually bounce off harmlessly.

    The US Airways flight hit the birds at 3,000 feet, the NTSB says. That caused a total engine failure, and the plane hit the river 3½ minutes later.

    "Brace! Brace! Head down!" the flight attendants shouted to the passengers.

    Then, they were in the water. The flight attendants likened it to a hard landing - nothing more. There was one impact, no bounce, then a gradual deceleration.

    "Neither one of them realized that they were in the water," Higgins said.

    The plane came to a stop. The captain gave a one-word command, "Evacuate."


    ASTOUNDING!!
     
  10. solofast

    solofast Formula 3

    Oct 8, 2007
    1,773
    Indianapolis
    A wing can stall at any airspeed, but if your speed is up it takes a larger load factor (bigger g's) to stall it, and most GA pilots get real squeamish pulling over 2 g's or so. And yes you could stall any airplane at any speed, but above maneuver speed, the wings will come off first! (Ok, that's an exaggeration, there is a 1.5 safety factor on that number, but you have exceeded the maximum certified load rating for the airplane at that point) And BTW at manuever speed you can bank at a 75 degree angle, pull 3.8 g's and be right at stalll.

    Here is a link to a study and a series of flight tests that were done on turning back to the airport after an engine failure. I had recalled that a fairly tight turn was the optimal rate of cranking around, but it appears that the actual optimal bank angle for minimum altitude loss is around 45 degrees, and that airspeed should be lower than I would like, (1.2 v stall) but there are other variables in place that might make you want to keep a bit of airspeed in your pocket if you have the altitude to pull it off. Take a look at this slide show, it is pretty illuminating.

    http://williams.best.vwh.net/turnback_seminar_Oct_2008.pdf

    500 ft agl was the minimum altitude from which you could, theoretically make it back (no wind condition in a C172), if you turn at a 45 degree angle of bank and kept the airspeed at about 1.2x stall speed (which is really slow but was optimal). More speed is safer, but it burns up altitude, so you need to know where you are and how much altitude you need to get back to the airport. In the study they found that in order to avoid overrunning the runway landing downwind from altitudes above the minimum, that they had to "S" turn to burn off altitude, so a faster turn with a loss of more altitude is actually better, but you have to have the altitude to burn when things get quiet. The relative skill level required for this is higher than a lot of maneuvers, but this study shows that with experienced (above 200 hrs TT) and educated pilots, that the success rate for returns in the simulator was 100%. For unskilled or uneducated pilots the success rate for returns was dismal, most of them crashed.

    Above 900 ft agl, if you are in the pattern or on a departure, you should be thinking about going back. At 600 agl you are going to have to be a pretty good stick to make it back, at 500 agl, if your name is Bob Hoover, you might barely make it back. What also was surprising in the study was the effect of headwinds, where a good headwind actually made it a lot easier to get back to the runway, and with a strong headwinds, it could be done from as low as 300 ft! As they noted in the study this was for a 172, each airplane has its own set of characteristics and high performance airplanes could take more or less, depending on the configuration and glide ratios.

    For each takeoff you should KNOW what altitude you need to make it back to the runway and if you aren't there and things get quiet you are landing straight ahead. I hadn't really thought about it a lot, but I will keep what I learned today about it and have go back/no go back altitude picked out before I push the throttle all the way in...

    I find that an awful lot of pilots really have no idea what the limits of the airplane are. They fly a lot of gentle turns, and straight and level, but don't have a good feel for what you can do with the airplane when you have to.
     
  11. CRUSING

    CRUSING Karting

    Oct 31, 2002
    235
    Jupiter, FL
    Interesting post!

    I will tell you that I would much rather take my chances putting a small plane down straight ahead in a flat area than risk a stall spin. Used to take students up to 3000 feet and have them climb full power for 500' then pull power to idle and have them pull a 180 to see if they could theoretically make it back to the runway. It is quite difficult and you would have to be very good and very calm to pull it off.

    Just like in LGA, the pilots made a quick decision to not try to make an airport... they had time to focus on landing and not on trying to make an airport. They didn't divert their attention from putting it down smooth. Looks like they committed and went with it with very good results.
     
  12. Bob Parks

    Bob Parks F1 Veteran
    Consultant

    Nov 29, 2003
    8,018
    Shoreline,Washington
    Full Name:
    Robert Parks
    I think that I related this incident once before but I will do it again.
    The only successful deadstick 180 that I ever saw was accomplished by my instructor when he had a student starting his dual x-country. They took off in a Cessna 140 and were not attaining the altitude that they should have at the end of the runway, where I was at the time. The engine sounded intermittenly rough and quit when they were at most 300 feet alt. The airplane looked like it had hit a trip wire. The nose pitched down to the vertical and while the airplane descended it made a smooth roll to the right until it was 180 deg. to its original line of flight and started a smooth pullout . It hit the ground hard in a three point attitude in tall grass and sort of disappeared. We heard a loud bang and when we got to it we could see that they hit the only log left over from when the field was cleared by the military in 1941. The landing gear torque box was swiveled back up into the fuselage and hurt the backs of both occupants but they were out of the airplane okay.
    The instructor had the student sitting in the grass while he was yelling at him, "DON'T EVER DO WHAT I JUST DID!"
    When we talked to the student he said that Bobby, the instructor, hit the wheel with both hands immediately pushing it into the instrument panel and turned the airplane while they were headed straight down and barely made a pullout.. It would have been successful if it hadn't been for the log in the tall grass.
    When I asked Bobby about it he said that he figured that it was going to happen some day and he already had a plan. To go straight ahead would have taken them into a forest of poles, wires, and restaurants. We found a tinnerman clip in one of the cylinders that had broken a valve and subsequently scrambled the engine.
     
  13. md88plt

    md88plt Karting
    BANNED

    Mar 4, 2008
    201
    usa
    Full Name:
    dc
    Captains are paid for their decisions and in this situation his discision was pretty much given to him. Ditch straight a head and follow evacution procedures. A left turn back to LGA it would have been disaster.

    The flight attendants need mega kudos.
     

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