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  • accident in Knoxville, IA

    https://app.ntsb.gov/pdfgenerator/Re...Final&IType=LA
    http://www.kcci.com/article/emergenc...reated/9519613

    I am a bit surprised at their trying to get 135hp by adding a turbo to the Rotax 912 ULS. Sounds like this one definitely had a turbo-related issue.

  • #2
    Hmph. Hot-rodding a 1200 cc engine to make 135 hp? Really?

    Comment


    • #3
      Please understand I wasn't there and am not being critical of the pilots decisions.

      I often spend time with students trying to learn from others misfortune and reinforce my somewhat extensive safety precautions.

      I feel it is best to only fly passengers with a properly running gyroplane.
      The continuing challenges with the engine would have restricted me to flying the pattern solo until I had the issues resolved.

      Part of becoming familiar with an airport is to look for emergency landing spots and identify obstructions (wires in this case).

      At 500 feet agl I can glide 1,500 feet to find a suitable emergency landing zone. The runway at OXV is 75 feet wide and 4,000 feet long. There are lots of open fields at the departure end of runway 15.
      https://www.google.com/maps/@41.2984.../data=!3m1!1e3

      I assume the engine is going to go quiet on every takeoff and prepare for that.

      I do not need to check the altimeter to see that I am descending.

      Part of the takeoff procedure is to make note of the rate of climb with the vertical speed indicator.

      I suspect earlier recognition of the problem would have allowed them to return to the airport.

      I feel flying closed traffic the pattern should always be within gliding distance of the runway.

      Before I leave the runway environment I check that the temperatures and pressures are in the green.

      I suspect the engine tachometer and manifold pressure gage provided information that the engine was not at takeoff power long before they left the runway environment.

      I wasn't there so I don't know what other challenges existed.

      These are just some thoughts to perhaps make your takeoff procedures safer.
      Last edited by Vance; 04-20-2018, 07:55 AM.
      Regards, Vance Breese Gyroplane CFI http://www.breeseaircraft.com/

      Comment


      • #4
        was this last year? NTSB report is dated 2017?
        Don Randle
        Gyroplane CFI

        "Flying a Gyro is the most fun you can have with your clothes on!"

        Comment


        • #5
          Yes it was last year Don Randle.

          The factual report was recently issued.
          Regards, Vance Breese Gyroplane CFI http://www.breeseaircraft.com/

          Comment


          • #6
            When turbocharging an engine you can gain 7% in HP for every 1 lb of boost,a intercooler is not needed with only 5-6 lbs of boost,

            The more pressure that's put on the engine the less reliable it becomes,there is a breaking point for reilabllity Vs HP gain.

            A little 1200 cc engine will have smaller/weaker parts,ie the crankshaft.rods ,pistons and valve train.I would think that much HP is

            taking it to its limits.

            Also turbocharging an engine with carbs is a really bad idea to me.The carbs would have to be designed to work with external

            air pressure applied to them as opposed to pulling a vacuum to operate them properly.
            Best Regards,
            Eddie Sigman,Polvadera,nm
            (575) 835-4921

            Comment


            • #7
              The 912 ULS is a 1352 cc engine. The 914 is 1211 cc, basically, a turbo'd 912 UL. All three use the same pressed crank which seems to be a weak link, especially for those with upped power. Not a huge point here, just clarification.

              Comment


              • #8
                Originally posted by magknight View Post
                The 912 ULS is a 1352 cc engine. The 914 is 1211 cc, basically, a turbo'd 912 UL. All three use the same pressed crank which seems to be a weak link, especially for those with upped power. Not a huge point here, just clarification.
                A point of note is that Rotax pushes that crankshaft only to 115hp in the 914. Not to the 135 hp that Xenon pushes it to.
                When they decided to go to make the 915 at 135hp, they redesigned the whole thing and went to fuel injection to eliminate the Carbs running on turbo boost issue.

                Comment


                • #9
                  Up to 125 HP the crank should be able to handle with reserve for safety a bit. 135 HP IMO requires welding and rebalancing the crank.
                  915iS is not ready for fixed pitch prop or ground adjustable prop. The whole mapping in the ECU is done for a constant speed prop. There is a single lever operation constant speed prop being developed by MT prop from Germany using a Searey Technology Demobstrator here and I have had extensive hours long conversation with the engineer helping do it.
                  Min about 6 months time Rotax plans to have an ECU mapping appropriate for a ground adjustable or fixed pitch prop done. Instead of getting 141 full HP,we may see only 135 hp out of it

                  Comment


                  • #10
                    Thanks for the update Fara.
                    Best Regards,
                    Eddie Sigman,Polvadera,nm
                    (575) 835-4921

                    Comment


                    • #11
                      Glad they walked away from that one.
                      Vance made several valid critical points.
                      A gyro engine out from 500' AGL over pastures shouldn't result in a wrecked machine.
                      Lots to learn from this incident.


                      ______
                      Please understand I wasn't there and am not being critical of the pilots decisions.
                      A woman I knew had a little boy who hadn't much nuance in his interpersonal communication, and would often blurt out rude things to people.
                      So, she taught him to say, "I don't mean to be rude, but ______." He would reliably preface with that, and then say the same rude thing, lol.

                      When Vance pointed out that the pilot shouldn't have flown with a passenger with a funky engine problem, didn't early enough discern his looming trouble,
                      apparently didn't know he was descending until he saw his VSI, and missed ample safe landing spots south of Runway 15, etc., it is patently criticizing the pilot's decisions.

                      I've done so many times on the forum. We generally hope to criticize in an empathetic and helpful way.
                      But let's simply call criticism for what it is, vs. trying to couch it in transparently pious terms and thus allege that we aren't criticizing at all.
                      It comes across to me as phony.

                      Thanks,
                      Kolibri



                      Last edited by Kolibri; 06-25-2018, 02:38 PM.
                      PP - ASEL complex (Piper 180, C206, RV-7A), SP - Gyro (Calidus, RAF, SC2), soloed in gliders; checkride soon

                      Wasn't happy with my RAF's pitch instability, so I installed a Boyer H-Stab to my great satisfaction!

                      "
                      When an honest but mistaken man learns of his error, he either ceases to be mistaken -- or he ceases to be honest."

                      Comment


                      • #12
                        Originally posted by Kolibri View Post
                        Glad they walked away from that one.
                        Vance made several valid critical points.
                        A gyro engine out from 500' AGL over pastures shouldn't result in a wrecked machine.
                        Lots to learn from this incident.


                        ______


                        A woman I knew had a little boy who hadn't much nuance in his interpersonal communication, and would often blurt out rude things to people.
                        So, she taught him to say, "I don't mean to be rude, but ______." He would reliably preface with that, and then say the same rude thing, lol.

                        When Vance pointed out that the pilot shouldn't have flown with a passenger with a funky engine problem, didn't early enough discern his looming trouble,
                        apparently didn't know he was descending until he saw his VSI, and missed ample safe landing spots south of Runway 15, etc., it is patently criticizing the pilot's decisions.

                        I've done so many times on the forum. We generally hope to criticize in an empathetic and helpful way.
                        But let's simply call criticism for what it is, vs. trying to couch it in transparently pious terms and thus allege that we aren't criticizing at all.
                        It comes across to me as phony.

                        Thanks,
                        Kolibri


                        I have studied enough accidents and been in enough difficult situations that I would never imagine that I knew what was in the mind of someone where something didnít work out.

                        I donít know what should have been done or why the pilot did what he did.

                        I feel any emergency landing in any aircraft is a challenging situation and I would not suggest I could have done it better.

                        I will say where I suspect things went amiss and try to identify the accident chain.

                        I feel there is value in the thought process even I am wrong.

                        The Pilot is not my client and it is not my job to teach him how I think.
                        Regards, Vance Breese Gyroplane CFI http://www.breeseaircraft.com/

                        Comment


                        • #13
                          Kolibri,
                          Vance was polite and showed restraint in my opinion. Did you read the report? Read pages 4 and 5 please. They had engine problems for the last 37 hours of flying.

                          Let me summarized the report facts that jump out at me at the risk of being rude:

                          - Built to 51% rule in four 12 hour days - really?
                          - No annual recorded in the log book after 300 + hours on the aircraft.
                          - Neither of the two brothers knew what the "turbo" knob function did but their excuse is that they never got a book for the turbo kit. The dealer also stated that the manufacturer didn't provide any instructions for the turbo kit to the dealer.
                          - claimed that it had run flawlessly for 37 hours after changing floats but go on to talk about repeated manifold probe problems

                          I am sorry but any pilot who BUILDS an experimental aircraft and doesn't know every nut, bolt, switch, and knob function is not taking his life or the life of other souls on board seriously. I think the pilot did well to put it down but the signs were there to stop flying it and haul it 100 miles back to the dealer! Put me in the rude camp too.

                          Comment


                          • #14
                            I donít know what should have been done . . .
                            I feel any emergency landing in any aircraft is a challenging situation and I would not suggest I could have done it better.
                            That's not what came through to me about your criticism, a criticism by the way that I wasn't objecting to.
                            I objected only to its "I'm not judging the pilot" qualifier which rang false to me.

                            Of course you knew what should have been done . . . you enunciated very clearly several undone/poorly done items.
                            And, you certainly implied that one c/should have landed better. (Partial power from 500' AGL above pastures? What's the big deal?)
                            They should have known safe paths after takeoff from their own airport, as you pointed out. I agree.

                            Look, they screwed up on many levels. It's not wrong, or evil, or sh*tty to simply say so.
                            Criticism was indeed called for. When it is, let's not whitewash that we're not being critical. This is all I meant.

                            _____
                            HighAltitude, my point was not that criticism ("rudeness") was wrong, or avoidable.
                            Sometimes it's necessary. Be polite, of course, but don't feign that it's noncritical.

                            Regards,
                            Kolibri
                            Last edited by Kolibri; 06-25-2018, 08:09 PM.
                            PP - ASEL complex (Piper 180, C206, RV-7A), SP - Gyro (Calidus, RAF, SC2), soloed in gliders; checkride soon

                            Wasn't happy with my RAF's pitch instability, so I installed a Boyer H-Stab to my great satisfaction!

                            "
                            When an honest but mistaken man learns of his error, he either ceases to be mistaken -- or he ceases to be honest."

                            Comment


                            • #15
                              Originally posted by Kolibri View Post

                              That's not what came through to me about your criticism, a criticism by the way that I wasn't objecting to.
                              I objected only to its "I'm not judging the pilot" qualifier which rang false to me.

                              Of course you knew what should have been done . . . you enunciated very clearly several undone/poorly done items.
                              And, you certainly implied that one c/should have landed better. (Partial power from 500' AGL above pastures? What's the big deal?)
                              They should have known safe paths after takeoff from their own airport, as you pointed out. I agree.

                              Look, they screwed up on many levels. It's not wrong, or evil, or sh*tty to simply say so.
                              Criticism was indeed called for. When it is, let's not whitewash that we're not being critical. This is all I meant.

                              _____
                              HighAltitude, my point was not that criticism ("rudeness") was wrong, or avoidable.
                              Sometimes it's necessary. Be polite, of course, but don't feign that it's noncritical.

                              Regards,
                              Kolibri
                              I have no control of what you read into the things a write and I don't want to diminish the learning opportunity here by pretending to know it all.

                              If you imagine you would not make these errors in my opinion you are being dishonest with yourself and missing a learning opportunity.

                              I don't know what was in the field or why the landing didn't work out and neither do you. I feel your question; "What was the big deal?" showcases your ignorance and inexperience.

                              When I had my last FAA check ride for my class two medical statement of demonstrated ability he didn't have me actually land in the fields because despite what you imagine that would be dangerous. He wanted to see if despite my monocular vision I had the knowledge and skill to set up an emergency landing. We did the engine at idle to the ground over the runway to SIMULATE an emergency landing to test my skills.

                              Pilots with more skill and experience than I have put together accident chains and I suspect they were able to justify each decision in their mind.

                              I have put together accident chains and was saved by luck from the consequences of my errors. One day my luck may run out.

                              In my opinion your unwillingness to recognize your own poor decisions makes it harder for you to learn and grow.

                              I feel imagining you would never do anything that stupid and you have the skills to make every emergency landing work out limits your ability to learn from accident reports and your own experiences.

                              I hope pilots here will learn from thinking about this accident openly and honestly and will not be sidetracked by your desire to make others appear wrong.

                              There are links of this accident chain that I would have done differently; that does not make me right or the accident pilot wrong.
                              Last edited by Vance; 06-25-2018, 10:43 PM.
                              Regards, Vance Breese Gyroplane CFI http://www.breeseaircraft.com/

                              Comment

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