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Lear 35 down approaching Teterboro

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  • #31
    Originally posted by 3WE View Post
    LOL- it's beautiful making half-donkey-ass-hat posts after a very quick scan of the flying article, and having Gabe do the deep dive read. I owe you a beer- on my second scan of the article, I did not see ceiling and visibility.

    Seeing that ceiling / visibility is a non issue...I also see that I was right that 5 miles was a bit much since 4 miles is standard...

    OK, good...I get it...the 4 miles (to me) seems like a fat, dumb and happy figure. I am pretty sure I have seen a 3 mile-or-so, near-90-degree base-to-final turn while riding an MD-80, heading West and then South into KKCI...nice gentle bank...plenty of time to straighten it out on final...speed under control...solid airmanship. (Yeah, sure, my foffie side imagined them running a wingtip into the ground...but the reality was Fat, Dumb, Happy, Stabilized).

    So, the guy broke it off 1 mile out...I concur that is too tight. I do still stand by my 'gross deviation from really fundamental fundamentals'...So, maybe it's 1) Don't bank the hell out of a jet (especially down low), and 2) Fast planes will get ahead of you if you are behind. I can't totally discount the wind, but what...without the wind, they would have only needed an 85-degree bank?
    The problem is that there are miles and miles. If you are approaching 06 and start the right turn 4 miles out, the point where you START THE TURN will be barely 2 and a little miles out of 01. By when you finish the right turn you will be in a 2 miles-out base, then you need to turn 90 deg to the left and you'll line up at about 1.5 miles out with some 500 ft AGL.

    Start right turn the turn 1 mile out of 06 and, if you make it tight, you will be heading directly toward the numbers, but perpendicular to the runway

    --- Judge what is said by the merits of what is said, not by the credentials of who said it. ---
    --- Defend what you say with arguments, not by imposing your credentials ---

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    • #32
      Originally posted by Evan View Post
      Ok, so, one mile out... .42NM radius turn to the right... .42NM radius turn to the left... nothing a self-respecting cowboy in a hotrod 35 can't handle...
      Oh, and that's with a 30 deg bank. That's not cowboy worthy. With 90 deg and 2.5G it's 0.1 NM radius.

      Not only that, it doesn't work either. Look at the graph, 1 mile out of 06 means much less than 1 mile out of 01. Even if you could do a 0 radius razor sharp right turn to establish yourself in a 100 deg heading base leg, you would be barely a few feet yards out of 01 by when you intercept the extended centerline of 01 for another zero-radius left turn to final.

      --- Judge what is said by the merits of what is said, not by the credentials of who said it. ---
      --- Defend what you say with arguments, not by imposing your credentials ---

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      • #33
        Originally posted by Gabriel View Post
        ...miles...miles....blah blah blah....miles...miles...mile...blah blah blah...
        Actually, I agree in that with 10 miles visibility, you ought to see the airport, and make nice big fat dumb and happy turns to line up...

        If the winds are severe and/or you cramp yourself a bit and gotta push your bank all the way to 30 degrees as part of cowboy improvisation...well, that's why you get the big bucks and have all the training and take the time to hand fly...and I always thought landing in good gusty winds were about as fun as it got...
        Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

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        • #34
          Originally posted by Evan View Post
          What's the climbing radius of a Lear 35 in a 90* bank? I guess its an ever tightening... spiral...
          Bank 90 degrees, pull (or not-pull) zero G, and the plane will describe a nice ballistic parabola (i.e. it will be basically a stone, or better a dart).

          Pull any G that you like other than zero and keep it constant, and that same parabola will be wrapped around a widening cone as the speed builds up.

          Curiosity/Quiz: Once the nose starts going down, if you are pulling up it requires continuous roll input to keep the bank angle at 90 deg, very significant roll input if the nose goes way down. Why?

          --- Judge what is said by the merits of what is said, not by the credentials of who said it. ---
          --- Defend what you say with arguments, not by imposing your credentials ---

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          • #35
            Originally posted by 3WE View Post
            Actually, I agree in that with 10 miles visibility, you ought to see the airport, and make nice big fat dumb and happy turns to line up...

            If the winds are severe and/or you cramp yourself a bit and gotta push your bank all the way to 30 degrees as part of cowboy improvisation...well, that's why you get the big bucks and have all the training and take the time to hand fly...and I always thought landing in good gusty winds were about as fun as it got...
            Yep. Agreed and concur.

            --- Judge what is said by the merits of what is said, not by the credentials of who said it. ---
            --- Defend what you say with arguments, not by imposing your credentials ---

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            • #36
              Originally posted by Gabriel View Post
              [ATTACH=CONFIG]7746[/ATTACH]

              and

              130 kts is 67 m/s. Sum of F radial = 2.5 x weight = m x acc radial Since weight = m x g (g = acceleration of the gravity =~ 10 m/s2) 2.5 x m x g = m x a So, a = 2.5 g = 25 m/s2, a = V2/r, so r = V2/a = (67 m/s)2 / 25 m/s2 = 179 m = 0.1 NM 1/Cos 30, stall speed will be sqrt(1.15) = 1.075 times, or 7.5% faster than, the 1G stall speed). Horizontal force = horizontal component of the lift = 0.58 x m x g = m x a a = 0.58 g a = v2/r r = v2/a = (67 m/s)2 / 0.58x10 m/s2 = 773 m or 0.42 NM At 15 deg bank 0.9 NM.
              Are you ardvark2zz?
              Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

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              • #37
                so basically the guy was trying to get a lear 35 at approach speed to act like an SU-35...and paid the ultimate price for his actions.

                Comment


                • #38
                  Originally posted by 3WE View Post
                  Are you ardvark2zz?
                  No. I don't have bunny ears.

                  --- Judge what is said by the merits of what is said, not by the credentials of who said it. ---
                  --- Defend what you say with arguments, not by imposing your credentials ---

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                  • #39
                    Originally posted by TeeVee View Post
                    so basically the guy was trying to get a lear 35 at approach speed to act like an SU-35...and paid the ultimate price for his actions.
                    An SU-35 at a similar bank and altitude might have done the same thing...
                    Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

                    Comment


                    • #40
                      Originally posted by 3WE View Post
                      An SU-35 at a similar bank and altitude might have done the same thing...
                      An Su-35 I don't know, but this Su-27 sliced several heads (but the pilots survived).


                      --- Judge what is said by the merits of what is said, not by the credentials of who said it. ---
                      --- Defend what you say with arguments, not by imposing your credentials ---

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                      • #41
                        ... thanks to a couple of well-timed feats of cowboy ejectmanship!
                        Be alert! America needs more lerts.

                        Eric Law

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                        • #42
                          Originally posted by Gabriel View Post
                          130 kts is 67 m/s.
                          At 90 deg of bank you will not hold the altitude or attitude no matter how much you "pull up" (because "up" is 100% horizontal), but that doesn't prevent you from making the turn, and all the lift will contribute to the radial acceleration needed to bend the speed vector (i.e. turn).
                          So let's say that you pull with a load factor of 2.5, that means that the lift will be 2.5 times the weight, and since the lift will be the only horizontal force with a radial component (neglecting an radial component that the thrust may have), we have

                          Sum of F radial = 2.5 x weight = m x acc radial
                          Since weight = m x g (g = acceleration of the gravity =~ 10 m/s2)
                          2.5 x m x g = m x a
                          So, a = 2.5 g = 25 m/s2

                          Now, in a circular motion, a = V2/r, so r = V2/a = (67 m/s)2 / 25 m/s2 = 179 m = 0.1 NM

                          How much with a 30 deg bank turn, assuming we hold the vertical speed constant?

                          Well, the vertical component of the lift needs to be equal to the weight.
                          The lift vector, tilted 30 degrees from the vertical, will need to measure weight / cos 30 deg.

                          1/cos 30 = 1.15 will be the load factor (and, if you are interested, the stall speed will be sqrt(1.15) = 1.075 times, or 7.5% faster than, the 1G stall speed). But we are not interested in anything of this.

                          The horizontal component of the lift, the one that will make the plane turn, will be lift x sin 30, and since lift was = weight / cos 30, we get that the horizontal component will be weight / cos 30 x sin 30 and that's weight x tan 30 = 0.58 times weight (and remember that weight = m x g).

                          Horizontal force = horizontal component of the lift = 0.58 x m x g = m x a
                          a = 0.58 g

                          a = v2/r

                          r = v2/a = (67 m/s)2 / 0.58x10 m/s2 = 773 m or 0.42 NM

                          At 15 deg bank it would be 0.9 NM.
                          Now I know where all of you "Senior members" got their 6,000 or 8,000 entries from... You always look when "the young boys" like me are not online, and then you ask your neighbor, who must be a mathematics professor, to write 300 or 900 entries...

                          Gabriel, but you don't wanna tell me that you do all this inflight, with only 1 of 2 engines, or only 2 of 4 engines running.

                          Flight Captain Chesley Sullenberger in his Airbus A320 is a hero in my eyes. Sullenberger deserves a golden star with a diamond because his decision is unique, until today. And why?
                          Because he knew what his a/c is able to do, in a jet with ZERO engines running. And he still knows how to get the best results in an A320. Evidence? "Sully The Film" (2016), where Sullenberger as senior advisor and reason for the film appeared at the end.

                          I don't think that he safely could've transformed his jet into a ship if he used 208 seconds for calculation. In German, it is called - it is late enough isn't it - Arschgefühl. You either have it for a special a/c type, or not.
                          Last edited by LH-B744; 2017-06-04, 05:17. Reason: Thank God, I have never sat in a jet with zero engines.
                          That's what airlines are good for, amongst others,
                          The Gold Member in the 747 club, 50 years since the first LH 747.
                          And constantly advanced, 744 and 748 /w upper and lower EICAS.
                          Aviation enthusiast, since more than 35 years with home airport EDDL.

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                          • #43
                            Argentina really mentions bank angles between 30 and 90°? Is this the first time when I doubt who at least once in his life has sat in a
                            CR7 (Bombardier Canadair Regional Jet 700) simulator?

                            I only mention it because imho, one of the very few civilian jets that have to be handled with more care than a CR7 is a Lear Jet, and in this case the Keyword is "smaller engines would still be big enough".

                            Why do you think, that, engineers, on the basis of the CR7, were only be able to develop the CR9, with exactly the same engine type?

                            Only because the CR7, with 20 seats less than the CR9, had too much horse power.

                            Since I am here, it is the same topic. I'd never buy a BMW limousine with more than 900 hp, or a 1978 VW Beetle with more than 350 hp.

                            If you have too much power, not the bank angle is your problem but your response time. In 2017, I haven't mentioned yet a story that happened when I became a JP member. So, here it is again.
                            4 young boys somewhere in the USA, the oldest only less than half as old as me (19?), tried to drive father's BMW M5, and they discovered a private airstrip with a hill at the end of the strip. The end of the story was, car parts and body parts that hung down from trees.

                            We still don't know the age of the two dead pilots in the Lear 35, or do we?

                            Leichtsinn und Übermut ist (meistens) eine Jugendsünde, but that's only my assumption.
                            That's what airlines are good for, amongst others,
                            The Gold Member in the 747 club, 50 years since the first LH 747.
                            And constantly advanced, 744 and 748 /w upper and lower EICAS.
                            Aviation enthusiast, since more than 35 years with home airport EDDL.

                            Comment


                            • #44
                              If I'm allowed to only add one very short comparison. Sometimes, my feeling about "too much power" is not only a feeling...

                              in anticlimactic order:

                              Lear 35: 2x 18 kN = 8 t ... thats a ratio of almost 5:1

                              Falcon F-16 (inaugurated 1978_): 1x 76 = 19 t ... that's a ratio of exactly 4:1, of course without afterburner.

                              Cr7: 2x 61 = 34 t ... thats a ratio of less than 4:1

                              ... ...
                              So, it seems as if Lear 35 pilots should be better educated than F-16 fighter pilots! Ejection seats included.

                              And I thought, the CR7 is quite powerful..
                              Last edited by LH-B744; 2017-06-04, 07:08. Reason: Until my first JP decade, I'll learn this 8_)
                              That's what airlines are good for, amongst others,
                              The Gold Member in the 747 club, 50 years since the first LH 747.
                              And constantly advanced, 744 and 748 /w upper and lower EICAS.
                              Aviation enthusiast, since more than 35 years with home airport EDDL.

                              Comment


                              • #45
                                Originally posted by LH-B744 View Post
                                Gabriel, but you don't wanna tell me that you do all this inflight, with only 1 of 2 engines, or only 2 of 4 engines running.
                                I totally agree. You need to do this stuff before flight. I mean, not do all the math I did, but you need to have a feeling of how much room you need to turn, how much you can safely bank at a given airspeed, etc...

                                And, most important, you shall not exceed your airplanes's and your personal limitations. If, in the middle of the flight where you cannot do all this math, you find that a normal turn is not enough to align with the runway, you don't tighten the turn, you go around. That's the equivalent of the pause button in the flight simulator. It gives you time to stay off trouble and evaluate your options.

                                And I don't know where you got that not all engines were running...

                                Flight Captain Chesley Sullenberger in his Airbus A320 is a hero in my eyes. Sullenberger deserves a golden star with a diamond because his decision is unique, until today. And why?
                                Because he knew what his a/c is able to do, in a jet with ZERO engines running. And he still knows how to get the best results in an A320. Evidence
                                Well, captain Chesley Sullenberg is my hero exactly for the opposite reason. He DID NOT know what plane was able to fo. He DID NOT know if he could reach La Guardia or Teterboro. In the aftermath, those 2 airports were marginally within gliding reach. But he DID NOT know that up there. So he is my hero because, having a couple of airports that maybe he could reach, he decided not to risk it and go for an outcome that was bad but was safer than what may have happened if he tried to reach an airport and failed. It is very tough for a pilot to take a decision to land off airport, in the water, knowing that there may be deaths, when you know that there are airports that MAYBE are within reach. But he still did it. He went for what he knew, even when it was bad, instead of going for a story with an open ending. And for that he is my hero.

                                As he said: "The Hudson was the only surface wide enough, long enough and smooth enough that I KNEW where within reach". The most important part of that statement is "I KNEW". If the investigation had demonstrated that La Guardia or Teterboro were not that marginal and were reasonably easy to reach, that would not have change my view of him. Up there and facing this hard decision, he didn't know what the investigation would reveal latter and he didn't have the means, tools or time to make that calculation himself.

                                --- Judge what is said by the merits of what is said, not by the credentials of who said it. ---
                                --- Defend what you say with arguments, not by imposing your credentials ---

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