Is there an abnormal condition that could have caused this fatal accident involving a stall?

The name of the pictureThe name of the pictureThe name of the pictureClash Royale CLAN TAG#URR8PPP











up vote
3
down vote

favorite












In 2009, a Grob 103 glider stalled and crashed at Richmond Field, Michigan, killing the passenger but not the pilot. (NTSB accident report: CEN09LA353)



The accident occurred after a failed winch launch; during the winch launch, the tow cable broke while the glider was about 400 feet AGL. The pilot correctly decided to turn around and return to the airport.



Here's what happened next, according to a statement the pilot later gave: "I could feel in the controls that something was not right and the glider was not responding in the manner that I am accustomed. There were none of the signs of a stall and the glider did not behave like it has any time that I have practiced stalls. Before I could determine the cause or take any action, the nose abruptly dropped and we dove toward the intended runway."



The NTSB report about the accident states that the probable cause of the accident was simply the pilot's failure to maintain adequate airspeed, resulting in a stall. Judging by this, the NTSB didn't seem to put much stock in the pilot's report that "something was not right".



Suppose that we take the pilot at their word, however. Is there any type of abnormal condition that might have caused a "feeling in the controls that something is not right", and which could cause the nose to drop with "none of the signs of a stall" occurring beforehand?










share|improve this question























  • Please, If possible try to find out if PIC manged to detach the broken cable
    – jean
    11 mins ago














up vote
3
down vote

favorite












In 2009, a Grob 103 glider stalled and crashed at Richmond Field, Michigan, killing the passenger but not the pilot. (NTSB accident report: CEN09LA353)



The accident occurred after a failed winch launch; during the winch launch, the tow cable broke while the glider was about 400 feet AGL. The pilot correctly decided to turn around and return to the airport.



Here's what happened next, according to a statement the pilot later gave: "I could feel in the controls that something was not right and the glider was not responding in the manner that I am accustomed. There were none of the signs of a stall and the glider did not behave like it has any time that I have practiced stalls. Before I could determine the cause or take any action, the nose abruptly dropped and we dove toward the intended runway."



The NTSB report about the accident states that the probable cause of the accident was simply the pilot's failure to maintain adequate airspeed, resulting in a stall. Judging by this, the NTSB didn't seem to put much stock in the pilot's report that "something was not right".



Suppose that we take the pilot at their word, however. Is there any type of abnormal condition that might have caused a "feeling in the controls that something is not right", and which could cause the nose to drop with "none of the signs of a stall" occurring beforehand?










share|improve this question























  • Please, If possible try to find out if PIC manged to detach the broken cable
    – jean
    11 mins ago












up vote
3
down vote

favorite









up vote
3
down vote

favorite











In 2009, a Grob 103 glider stalled and crashed at Richmond Field, Michigan, killing the passenger but not the pilot. (NTSB accident report: CEN09LA353)



The accident occurred after a failed winch launch; during the winch launch, the tow cable broke while the glider was about 400 feet AGL. The pilot correctly decided to turn around and return to the airport.



Here's what happened next, according to a statement the pilot later gave: "I could feel in the controls that something was not right and the glider was not responding in the manner that I am accustomed. There were none of the signs of a stall and the glider did not behave like it has any time that I have practiced stalls. Before I could determine the cause or take any action, the nose abruptly dropped and we dove toward the intended runway."



The NTSB report about the accident states that the probable cause of the accident was simply the pilot's failure to maintain adequate airspeed, resulting in a stall. Judging by this, the NTSB didn't seem to put much stock in the pilot's report that "something was not right".



Suppose that we take the pilot at their word, however. Is there any type of abnormal condition that might have caused a "feeling in the controls that something is not right", and which could cause the nose to drop with "none of the signs of a stall" occurring beforehand?










share|improve this question















In 2009, a Grob 103 glider stalled and crashed at Richmond Field, Michigan, killing the passenger but not the pilot. (NTSB accident report: CEN09LA353)



The accident occurred after a failed winch launch; during the winch launch, the tow cable broke while the glider was about 400 feet AGL. The pilot correctly decided to turn around and return to the airport.



Here's what happened next, according to a statement the pilot later gave: "I could feel in the controls that something was not right and the glider was not responding in the manner that I am accustomed. There were none of the signs of a stall and the glider did not behave like it has any time that I have practiced stalls. Before I could determine the cause or take any action, the nose abruptly dropped and we dove toward the intended runway."



The NTSB report about the accident states that the probable cause of the accident was simply the pilot's failure to maintain adequate airspeed, resulting in a stall. Judging by this, the NTSB didn't seem to put much stock in the pilot's report that "something was not right".



Suppose that we take the pilot at their word, however. Is there any type of abnormal condition that might have caused a "feeling in the controls that something is not right", and which could cause the nose to drop with "none of the signs of a stall" occurring beforehand?







accidents glider stall sailplane






share|improve this question















share|improve this question













share|improve this question




share|improve this question








edited 39 secs ago

























asked 2 hours ago









Tanner Swett

772516




772516











  • Please, If possible try to find out if PIC manged to detach the broken cable
    – jean
    11 mins ago
















  • Please, If possible try to find out if PIC manged to detach the broken cable
    – jean
    11 mins ago















Please, If possible try to find out if PIC manged to detach the broken cable
– jean
11 mins ago




Please, If possible try to find out if PIC manged to detach the broken cable
– jean
11 mins ago










2 Answers
2






active

oldest

votes

















up vote
5
down vote













Possibly a Center of Gravity beyond the aft limit could do it, but with 2 adults on board I don't think that's likely unless the person up front was really small and the PIC failed to load ballast to bring the front seat weight up to the minimum. The NTSB report doesn't say anything about loading so that seems to be a non-issue and there were no other anomalies with the airplane that they could find. Possibly really bad bug contamination on the leading edges could also affect the stall behaviour and maybe that could've been a factor the investigator overlooked. Pretty unusual to see gliders with bugs allowed to accumulate that badly, however.



One of the problems with winch launches is when a cable breaks at 400 ft like that, you are in the worst possible place to be, directly over the middle of the runway. There is no way to get aligned with a runway to land without a fair bit of maneuvering and turning, and you're high enough that landing more directly toward an off-airport field is out of the question, since 400 feet is a lot of altitude to play with in a 35:1 glider, so psychologically the tendency is to be hell bent on landing on the grass directly below you one way or another. With that kind of unpleasant surprise with the stress level dialed up, it's likely the pilot simply did not perceive the pre-stall behaviour while concentrating on getting lined up.



In gliders the pre-stall cues can be fairly subtle by power plane standards, obvious enough during deliberate practice but easy to miss when mentally loaded up with a life and death do-it-now task. So if I was going to bet a large sum of money on a likely cause, I'd go with the pilot stalling and spinning an otherwise normal glider from failure to maintain flying speed while maneuvering, regardless of what his recollection is.






share|improve this answer



























    up vote
    3
    down vote













    Your question:




    Suppose that we take the pilot at their word, however. Is there any type of abnormal condition that might have caused a "feeling in the controls that something is not right", and which could cause the nose to drop with "none of the signs of a stall" occurring beforehand?




    A couple of thoughts:



    1. In a 60 degree level bank turn, stall speed increases by about 40%.


    2. See below for information regarding indications of an approaching stall in the G103. (from the G 103 C Twin III Acro manual)


    G103 Flight Manual



    enter image description here



    Here is a copy of the manual for the Grob G103 Twin III Acro: G103 manual



    Here is a copy of the NTSB report I believe covers this accident: Grob 103 Accident - NTSB Identification: CEN09LA353






    share|improve this answer




















    • I don't quite understand the yellow highlighted note. Is it saying that at max weight and forward CoG position, the limit on elevator control deflection will act to limit the angle of attack, making it impossible to even get close enough to a stall for tail buffeting to occur?
      – Tanner Swett
      2 mins ago










    Your Answer




    StackExchange.ifUsing("editor", function ()
    return StackExchange.using("mathjaxEditing", function ()
    StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix)
    StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
    );
    );
    , "mathjax-editing");

    StackExchange.ready(function()
    var channelOptions =
    tags: "".split(" "),
    id: "528"
    ;
    initTagRenderer("".split(" "), "".split(" "), channelOptions);

    StackExchange.using("externalEditor", function()
    // Have to fire editor after snippets, if snippets enabled
    if (StackExchange.settings.snippets.snippetsEnabled)
    StackExchange.using("snippets", function()
    createEditor();
    );

    else
    createEditor();

    );

    function createEditor()
    StackExchange.prepareEditor(
    heartbeatType: 'answer',
    convertImagesToLinks: false,
    noModals: false,
    showLowRepImageUploadWarning: true,
    reputationToPostImages: null,
    bindNavPrevention: true,
    postfix: "",
    noCode: true, onDemand: true,
    discardSelector: ".discard-answer"
    ,immediatelyShowMarkdownHelp:true
    );



    );













     

    draft saved


    draft discarded


















    StackExchange.ready(
    function ()
    StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2faviation.stackexchange.com%2fquestions%2f55910%2fis-there-an-abnormal-condition-that-could-have-caused-this-fatal-accident-involv%23new-answer', 'question_page');

    );

    Post as a guest






























    2 Answers
    2






    active

    oldest

    votes








    2 Answers
    2






    active

    oldest

    votes









    active

    oldest

    votes






    active

    oldest

    votes








    up vote
    5
    down vote













    Possibly a Center of Gravity beyond the aft limit could do it, but with 2 adults on board I don't think that's likely unless the person up front was really small and the PIC failed to load ballast to bring the front seat weight up to the minimum. The NTSB report doesn't say anything about loading so that seems to be a non-issue and there were no other anomalies with the airplane that they could find. Possibly really bad bug contamination on the leading edges could also affect the stall behaviour and maybe that could've been a factor the investigator overlooked. Pretty unusual to see gliders with bugs allowed to accumulate that badly, however.



    One of the problems with winch launches is when a cable breaks at 400 ft like that, you are in the worst possible place to be, directly over the middle of the runway. There is no way to get aligned with a runway to land without a fair bit of maneuvering and turning, and you're high enough that landing more directly toward an off-airport field is out of the question, since 400 feet is a lot of altitude to play with in a 35:1 glider, so psychologically the tendency is to be hell bent on landing on the grass directly below you one way or another. With that kind of unpleasant surprise with the stress level dialed up, it's likely the pilot simply did not perceive the pre-stall behaviour while concentrating on getting lined up.



    In gliders the pre-stall cues can be fairly subtle by power plane standards, obvious enough during deliberate practice but easy to miss when mentally loaded up with a life and death do-it-now task. So if I was going to bet a large sum of money on a likely cause, I'd go with the pilot stalling and spinning an otherwise normal glider from failure to maintain flying speed while maneuvering, regardless of what his recollection is.






    share|improve this answer
























      up vote
      5
      down vote













      Possibly a Center of Gravity beyond the aft limit could do it, but with 2 adults on board I don't think that's likely unless the person up front was really small and the PIC failed to load ballast to bring the front seat weight up to the minimum. The NTSB report doesn't say anything about loading so that seems to be a non-issue and there were no other anomalies with the airplane that they could find. Possibly really bad bug contamination on the leading edges could also affect the stall behaviour and maybe that could've been a factor the investigator overlooked. Pretty unusual to see gliders with bugs allowed to accumulate that badly, however.



      One of the problems with winch launches is when a cable breaks at 400 ft like that, you are in the worst possible place to be, directly over the middle of the runway. There is no way to get aligned with a runway to land without a fair bit of maneuvering and turning, and you're high enough that landing more directly toward an off-airport field is out of the question, since 400 feet is a lot of altitude to play with in a 35:1 glider, so psychologically the tendency is to be hell bent on landing on the grass directly below you one way or another. With that kind of unpleasant surprise with the stress level dialed up, it's likely the pilot simply did not perceive the pre-stall behaviour while concentrating on getting lined up.



      In gliders the pre-stall cues can be fairly subtle by power plane standards, obvious enough during deliberate practice but easy to miss when mentally loaded up with a life and death do-it-now task. So if I was going to bet a large sum of money on a likely cause, I'd go with the pilot stalling and spinning an otherwise normal glider from failure to maintain flying speed while maneuvering, regardless of what his recollection is.






      share|improve this answer






















        up vote
        5
        down vote










        up vote
        5
        down vote









        Possibly a Center of Gravity beyond the aft limit could do it, but with 2 adults on board I don't think that's likely unless the person up front was really small and the PIC failed to load ballast to bring the front seat weight up to the minimum. The NTSB report doesn't say anything about loading so that seems to be a non-issue and there were no other anomalies with the airplane that they could find. Possibly really bad bug contamination on the leading edges could also affect the stall behaviour and maybe that could've been a factor the investigator overlooked. Pretty unusual to see gliders with bugs allowed to accumulate that badly, however.



        One of the problems with winch launches is when a cable breaks at 400 ft like that, you are in the worst possible place to be, directly over the middle of the runway. There is no way to get aligned with a runway to land without a fair bit of maneuvering and turning, and you're high enough that landing more directly toward an off-airport field is out of the question, since 400 feet is a lot of altitude to play with in a 35:1 glider, so psychologically the tendency is to be hell bent on landing on the grass directly below you one way or another. With that kind of unpleasant surprise with the stress level dialed up, it's likely the pilot simply did not perceive the pre-stall behaviour while concentrating on getting lined up.



        In gliders the pre-stall cues can be fairly subtle by power plane standards, obvious enough during deliberate practice but easy to miss when mentally loaded up with a life and death do-it-now task. So if I was going to bet a large sum of money on a likely cause, I'd go with the pilot stalling and spinning an otherwise normal glider from failure to maintain flying speed while maneuvering, regardless of what his recollection is.






        share|improve this answer












        Possibly a Center of Gravity beyond the aft limit could do it, but with 2 adults on board I don't think that's likely unless the person up front was really small and the PIC failed to load ballast to bring the front seat weight up to the minimum. The NTSB report doesn't say anything about loading so that seems to be a non-issue and there were no other anomalies with the airplane that they could find. Possibly really bad bug contamination on the leading edges could also affect the stall behaviour and maybe that could've been a factor the investigator overlooked. Pretty unusual to see gliders with bugs allowed to accumulate that badly, however.



        One of the problems with winch launches is when a cable breaks at 400 ft like that, you are in the worst possible place to be, directly over the middle of the runway. There is no way to get aligned with a runway to land without a fair bit of maneuvering and turning, and you're high enough that landing more directly toward an off-airport field is out of the question, since 400 feet is a lot of altitude to play with in a 35:1 glider, so psychologically the tendency is to be hell bent on landing on the grass directly below you one way or another. With that kind of unpleasant surprise with the stress level dialed up, it's likely the pilot simply did not perceive the pre-stall behaviour while concentrating on getting lined up.



        In gliders the pre-stall cues can be fairly subtle by power plane standards, obvious enough during deliberate practice but easy to miss when mentally loaded up with a life and death do-it-now task. So if I was going to bet a large sum of money on a likely cause, I'd go with the pilot stalling and spinning an otherwise normal glider from failure to maintain flying speed while maneuvering, regardless of what his recollection is.







        share|improve this answer












        share|improve this answer



        share|improve this answer










        answered 1 hour ago









        John K

        9,0591028




        9,0591028




















            up vote
            3
            down vote













            Your question:




            Suppose that we take the pilot at their word, however. Is there any type of abnormal condition that might have caused a "feeling in the controls that something is not right", and which could cause the nose to drop with "none of the signs of a stall" occurring beforehand?




            A couple of thoughts:



            1. In a 60 degree level bank turn, stall speed increases by about 40%.


            2. See below for information regarding indications of an approaching stall in the G103. (from the G 103 C Twin III Acro manual)


            G103 Flight Manual



            enter image description here



            Here is a copy of the manual for the Grob G103 Twin III Acro: G103 manual



            Here is a copy of the NTSB report I believe covers this accident: Grob 103 Accident - NTSB Identification: CEN09LA353






            share|improve this answer




















            • I don't quite understand the yellow highlighted note. Is it saying that at max weight and forward CoG position, the limit on elevator control deflection will act to limit the angle of attack, making it impossible to even get close enough to a stall for tail buffeting to occur?
              – Tanner Swett
              2 mins ago














            up vote
            3
            down vote













            Your question:




            Suppose that we take the pilot at their word, however. Is there any type of abnormal condition that might have caused a "feeling in the controls that something is not right", and which could cause the nose to drop with "none of the signs of a stall" occurring beforehand?




            A couple of thoughts:



            1. In a 60 degree level bank turn, stall speed increases by about 40%.


            2. See below for information regarding indications of an approaching stall in the G103. (from the G 103 C Twin III Acro manual)


            G103 Flight Manual



            enter image description here



            Here is a copy of the manual for the Grob G103 Twin III Acro: G103 manual



            Here is a copy of the NTSB report I believe covers this accident: Grob 103 Accident - NTSB Identification: CEN09LA353






            share|improve this answer




















            • I don't quite understand the yellow highlighted note. Is it saying that at max weight and forward CoG position, the limit on elevator control deflection will act to limit the angle of attack, making it impossible to even get close enough to a stall for tail buffeting to occur?
              – Tanner Swett
              2 mins ago












            up vote
            3
            down vote










            up vote
            3
            down vote









            Your question:




            Suppose that we take the pilot at their word, however. Is there any type of abnormal condition that might have caused a "feeling in the controls that something is not right", and which could cause the nose to drop with "none of the signs of a stall" occurring beforehand?




            A couple of thoughts:



            1. In a 60 degree level bank turn, stall speed increases by about 40%.


            2. See below for information regarding indications of an approaching stall in the G103. (from the G 103 C Twin III Acro manual)


            G103 Flight Manual



            enter image description here



            Here is a copy of the manual for the Grob G103 Twin III Acro: G103 manual



            Here is a copy of the NTSB report I believe covers this accident: Grob 103 Accident - NTSB Identification: CEN09LA353






            share|improve this answer












            Your question:




            Suppose that we take the pilot at their word, however. Is there any type of abnormal condition that might have caused a "feeling in the controls that something is not right", and which could cause the nose to drop with "none of the signs of a stall" occurring beforehand?




            A couple of thoughts:



            1. In a 60 degree level bank turn, stall speed increases by about 40%.


            2. See below for information regarding indications of an approaching stall in the G103. (from the G 103 C Twin III Acro manual)


            G103 Flight Manual



            enter image description here



            Here is a copy of the manual for the Grob G103 Twin III Acro: G103 manual



            Here is a copy of the NTSB report I believe covers this accident: Grob 103 Accident - NTSB Identification: CEN09LA353







            share|improve this answer












            share|improve this answer



            share|improve this answer










            answered 1 hour ago









            757toga

            4,9521029




            4,9521029











            • I don't quite understand the yellow highlighted note. Is it saying that at max weight and forward CoG position, the limit on elevator control deflection will act to limit the angle of attack, making it impossible to even get close enough to a stall for tail buffeting to occur?
              – Tanner Swett
              2 mins ago
















            • I don't quite understand the yellow highlighted note. Is it saying that at max weight and forward CoG position, the limit on elevator control deflection will act to limit the angle of attack, making it impossible to even get close enough to a stall for tail buffeting to occur?
              – Tanner Swett
              2 mins ago















            I don't quite understand the yellow highlighted note. Is it saying that at max weight and forward CoG position, the limit on elevator control deflection will act to limit the angle of attack, making it impossible to even get close enough to a stall for tail buffeting to occur?
            – Tanner Swett
            2 mins ago




            I don't quite understand the yellow highlighted note. Is it saying that at max weight and forward CoG position, the limit on elevator control deflection will act to limit the angle of attack, making it impossible to even get close enough to a stall for tail buffeting to occur?
            – Tanner Swett
            2 mins ago

















             

            draft saved


            draft discarded















































             


            draft saved


            draft discarded














            StackExchange.ready(
            function ()
            StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2faviation.stackexchange.com%2fquestions%2f55910%2fis-there-an-abnormal-condition-that-could-have-caused-this-fatal-accident-involv%23new-answer', 'question_page');

            );

            Post as a guest













































































            Popular posts from this blog

            How to check contact read email or not when send email to Individual?

            Displaying single band from multi-band raster using QGIS

            How many registers does an x86_64 CPU actually have?