We are talking passed each other. Here is a simple explanation all of you can understand and it may not be my English misstating things..... Throw a frisbee into the wind and it will create lift and fly far far away. Now do the same with the wind. It flops. That's why you overshoot on landing with head wind. Any questions?
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Tue Feb 10, 2015 12:35 pm
Gabor
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I may have used the wrong terms which makes no difference in the outcome. If you are shooting and ILS and holding the 3 degree glide and have a groundspeed of 80knots due to a strong 30 KTS headwind at 2000ft the rate of descent required to maintain the glide is about 420fpm. When in the last 500ft the wind has decreased to 10KTS and now your groundspeed is 120 knots, a rate of descent of 640fpm is required which is more likes the reason for having to put the nose down and then reducing power to keep the correct speed or reducing power and then pitching down to keep the correct speed. If you kept your setting as is because of the less wind you;'d undershoot it! If it was the other way around the more head wind would make you over shoot it! There is no two ways about this guys. I have learned about this during my instrument rating. I had to freaking calculate this shit. Just sayin'.... Grab an instrument flying hand book it has to be in it. I am at work so I just punch a few words here as I get a chance. When I get home I'll find my books for you OK?
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A walk in the woods helps me relax and release tension. The fact that I am dragging a body should be entirely irrelevant! A simple thank you would have been enough for the morning coffee without all that "how did you get in here" nonsense.
Tue Feb 10, 2015 1:09 pm
Hellified
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I may have used the wrong terms which makes no difference in the outcome. If you are shooting and ILS and holding the 3 degree glide and have a groundspeed of 80knots due to a strong 30 KTS headwind at 2000ft the rate of descent required to maintain the glide is about 420fpm. When in the last 500ft the wind has decreased to 10KTS and now your groundspeed is 120 knots, a rate of descent of 640fpm is required which is more likes the reason for having to put the nose down and then reducing power to keep the correct speed or reducing power and then pitching down to keep the correct speed. If you kept your setting as is because of the less wind you;'d undershoot it! If it was the other way around the more head wind would make you over shoot it! There is no two ways about this guys. I have learned about this during my instrument rating. I had to freaking calculate this shit. Just sayin'.... Grab an instrument flying hand book it has to be in it. I am at work so I just punch a few words here as I get a chance. When I get home I'll find my books for you OK?
I think where we are missing each other, is if I have an engine failure in a gyro, I no longer look at my asi or anything else, I look where I am going to land and ai don't think of best glide slop, best rate of descent, rotor rpm...... I look at my ELZ and I control the machine until I am at the ELZ and do the best landing I can onto it..... the only 'instrument' I look at is the piece of wool (yaw string). If you have an engine out at less than 500' you have no time to think, you just do...... so the confusion for me, is I know at the altitude that I have left can either give me energy for a flare right below me, or I can lower the nose considerably and get the maximum speed I can, then convert that into a long ground effect run to where I have to flare for touchdown, if I have terrain suitable for that. What I discovered in my engine out on film, is that pointing a gyro at the ground, really nose down, the speed wont increase to high numbers, that is why I asked Lofty the other day, how fast (airspeed) can his machine get to in a 'dive' ...... I never tried with mine except the day of that outlanding, but I doubt if it got over 60kts.... I didn't look, I was busy
I do know that once at lake George I had another engine out, I was prolly 3 miles from the cars and my trailer and I didn't fancy walking a long distance, so I just went into a fairly steep nose down glide and upon getting to flare height with a lot of speed on, skimmed above the ground (which is like a pool table) and managed to finally flare and touch down only a mile or so from the cars, instead of 2.... but again, I didn't look at anything but the yaw string and looking for obsticles
Had I set up for some best glide angle, I would have had a 2 mile walk..... but by trading my altitude for airspeed, and then not doing a big flare from a steep descent, I used the energy slowly to get closer to the cars.
I know that my machine is nothing like a modern euro, but I think it is good to fly more by the seat of the pants and knowing what feels right, rather than having to be told by instruments if it is right or not. I know helis are different, rotor speed is everything.... but gyro rotors will do their own thing without any input from the pilot..... even if you flare above the shortest trees you can find and end up in a true verticle to the ground, until the rotors hit something, they will turn at the speed they need to...... that is why I love gyros...... the rotors may eventually hit something and beat themselves to bits, but you can steer the machine towards 'softer' things and be in complete control of the machine until they do hit something
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The frisbee example is a very poor one. When you throw a frisbee, say at 10MPH with a 10 MPH tail wind, it therefore has 0 IAS, therefore 0 lift, therefore it flops. If you throw it with the same strength, into wind it will have a 20 MPH airspeed therefore lift, and therefore stay aloft. Again my gyro is not a frisbee. I completely understand gradients etc., and yes it has been poorly stated, and English my be a problem etc, but it all changes nothing. If I am in my downwind leg on a pattern and I want to land on the numbers, I will turn earlier to base and final to hit those numbers if there is a strong headwind down the runway versus no wind or even a tailwind. (Then I would be flying with a headwind on 'downwind'). Same height on initial descent point, same approach speed etc, etc. There are two vectors horizontal and vertical. The time it takes for me to hit the ground from a given height at a given IAS with my engine off is a constant, irrespective of windspeed. At a given IAS my descent rate is unchanged whether I am pointed upwind or downwind, so I will hit the ground at the identical time, even though I will not hit the same point on the ground Just like a bullet shot horizontally is in the air for the exact same time no matter how fast it leaves the barrel. The only difference is that if the barrel speed is faster it will land further away because it travels further during the same length of time. Same with the gyro, the time I am above the ground will be unchanged for any given glide speed as the vertical component of this vector does not change (if there are no updrafts or downdrafts). Similarly, the horizontal component of my IAS is also a constant for any given IAS. The only thing that can change is my horizontal groundspeed based on the sum of my fixed horizontal airspeed and the windspeed which is variable. If I am flying into a headwind I will fly for the same time period at a slower groundspeed, than if I am flying with a tailwind. Distance = Velocity x Time. Same time, higher velocity horizontally over the ground, distance is further. Same time lower velocity horizontally over the ground, distance travelled will be less. You can introduce other variables for gradient, compensating by pushing stick forward or back changing IAS etc, but with a constant IAS and height, there's simply no question, pointed into wind distance to land is shorter than pointing with the wind. Unless Newton was wrong as well. I would suggest, though not argue, that even with a hell if you were not allowed to touch the collective and were instructed to maintain the same IAS as you auto rotated to the ground, the same would apply. And Muz, I understand all these things about making decisions on the spot in order to land in a desired spot, changing glide speed pulling up or pushing forward etc. But again, this is not about changing ANY variable except upwind or downwind. And if no other variables change one will land further away with a tailwind, than with a headwind. If I am wrong on this, I will definitely give up flying because I am clearly dangerous and have been doing everything completely opposite to the way I am supposed to.
Last edited by loftus on Tue Feb 10, 2015 2:28 pm, edited 1 time in total.
Tue Feb 10, 2015 2:06 pm
Gabor
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Wrong. Your gyro is a frisbee! I huge disc Jeff. What keeps that disc in the air is the moving air through your disc. The more air mover through more lift has been created. More lift equals longer glide path. This is simple math. Nothing more. Birdy is completely right! Your Rates of descent for a three-degree glide path vs. Ground Speed by the book! kts ..55 ..60..65 ..70 ..75 ..80 fpm 292 318 345 371 398 424 So you are flying at 55 kts in a calm condition and shooting an ILS approach holding a 292 foot per minute descent. You hit a freaking wind of 25 kts head on and it increases to 80 kts. Now you have to nose it over in order to make your ILS landing zone or you'd better call it a missed right there on the spot! You simply overshoot it. Birdy WINS! End of argument.
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A walk in the woods helps me relax and release tension. The fact that I am dragging a body should be entirely irrelevant! A simple thank you would have been enough for the morning coffee without all that "how did you get in here" nonsense.
Tue Feb 10, 2015 2:27 pm
Hillberg
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gab just a little idea in my head, little brain fart, and give me a chance i am not a pilot for the moment. just the way i think i can see it a little bit, exemple when i see the vidéo of the guy in the désert with is green mto sport flying hovering in big 30-35 kts head wind, he even can back up like he want , he can make a circle from his hovering spot and when he his at the top of is circle, he go back and réduce is altitude and when at the base of is cercle he put power and can répeat the same move or circle, he play hélicopter, anyway if no big wind , no hover, when the guy play hover stationary, if he want to land he have to réduce power and drop the nose, or he will not land, but for me you and birdy tell correct, bécause what you explain me is like the guy that hover with is head wind, you have to make what you tell or you will fly farther for longer, and i know an emergency landing with a head wind is not what the guy do, but just my little idea
Wrong. Your gyro is a frisbee! I huge disc Jeff. What keeps that disc in the air is the moving air through your disc. This is simple math. Nothing more. Birdy is completely right! Your Rates of descent for a three-degree glide path vs. Ground Speed by the book! kts 55 60 65 70 75 80 fpm 292 318 345 371 398 424 So you are flying at 55 kts in a calm condition and shooting an ILS approach holding a 292 foot per minute descent. You hit a freaking wind of 25 kts head on and it increases to 80 kts. Now you have to nose it over in order to make your ILS landing zone or you'd better call it a missed right there on the spot! You simply overshoot it. Birdy WINS! End of argument.
Yes, Gabor but assuming you throw the frisbee with the same strength it's AIRSPEED will be different into or with the wind.
I just don't get you guys. Read Birdy's post, there's nothing about changing glide slope, changing rate of descent etc. Just aiming for a point on the ground that one wants to 'glide' down to. Of course I understand that if you want to hit the same spot with a strong headwind versus a tailwind you will have to pitch forward or backward to keep the same glide path and hit that same spot. That is NOT what he said. We are not talking about the compensatory changes the pilot has to make in order to adjust for wind strength. What is implied in his statement, is that if one holds the same pitch, and therefore IAS, (not changing from 55-80 as you describe above) and one goes from a tailwind to a headwind, you will land further away and that is WRONG, it's the opposite. You are right, if you don't want to land further or closer away you will have to pitch the aircraft up or down and either increase or decrease airspeed to hit the same spot. I understand that, but his primary statement 'If your donk goes quiet and you setup for that spot that just happens to be at the bottom of the slope youv practiced many times, a head wind will have you overshoot, and a tail wind will see you fall short ' is still wrong. If you don't adjust your IAS to compensate, just the opposite will happen. Point being if I am aiming for a spot, and all of a sudden the wind picks up, unless I adjust my glide slope accordingly, I will undershoot, not overshoot. So maybe it's just poorly stated, misstated or should have been better qualified, but as stated it's wrong. If it's not wrong can you please explain to me why when I am flying in the pattern with a strong wind down the runway, and I set up my glide speed for 55kts, I have to turn base to final more directly abreast of the numbers, than if there is minimal wind. Remember, I said NOTHING about changing my pitch from 55- 80 or whatever. And my final attempt at explanation. Lets say I cut the throttle, and set up my gyro to a pitch of 55 in different situations. Imagine one could do it in a wind tunnel. Starting with zero headwind I will land somewhere out there further ahead of me. Now I turn up the fan and do absolutely nothing else. Remember I am keeping the pitch of my gyro at 55kts IAS throughout the exercise. I will land closer and closer in front of me to the point that if the wind is turned up to 55 knots, I will descend vertically and land immediately below me. And if I turn it up even more, I will actually move backwards and have a negative distance. So again, don't try to explain to me that I have to change pitch and IAS to reach the same spot with different wind speeds, I understand that, but nothing can convince me that if I keep the same pitch and IAS that turning up the headwind will make me land further away. If you are flying at 55knots IAS as you describe above in a descent, and the windspeed is 25 knots, your ground speed is 30 knots. If the windspeed picks up to 80knots and you keep up an IAS of 55kts, you will never reach your destination, it will blow you back and away from your destination at 25 knots in the opposite direction. That's why it takes longer to get somewhere in a headwind than it does in a tailwind.
Last edited by loftus on Tue Feb 10, 2015 4:57 pm, edited 1 time in total.
Tue Feb 10, 2015 4:39 pm
Hellified
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Jeff- You are not getting what Birdy is saying. I can tell you over the phone much quicker. Your last statement can be used as proof. I refuse to get in a back and forth typing war such as the "hover" topic was. Ha
Jeff- You are not getting what Birdy is saying. I can tell you over the phone much quicker. Your last statement can be used as proof.
217-419-4967.
I know I am not getting what Birdy was saying and I concede that; I'm happy to get things explained in a different way, just going to have to change the laws of physics to make me believe that if the windspeed is greater than my IAS, I am going anywhere but backwards.
Tue Feb 10, 2015 5:02 pm
Gabor
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'If your donk goes quiet and you setup for that spot that just happens to be at the bottom of the slope youv practiced many times, a head wind will have you overshoot, and a tail wind will see you fall short ' is still wrong.
Nope. He is absolutely right. You will overshoot.
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A walk in the woods helps me relax and release tension. The fact that I am dragging a body should be entirely irrelevant! A simple thank you would have been enough for the morning coffee without all that "how did you get in here" nonsense.
Tue Feb 10, 2015 5:06 pm
Hellified
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I didn't read the whole thing, but a quick look at birdys post looks like he is talking about completely different constraints which may have also followed into this thread.
Looks like Gabor is talking about heli autorotations which are very different constraints than normal power on gyro landings at a fixed airspeed which appears what Jeff is talking about.
Looks like birdy was talking about engine out which is also very different than normal power on fixed airspeed landings.
I might be wrong, although this looks to me like you are arguing about different topics or at least different boundary conditions.
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Tue Feb 10, 2015 5:25 pm
Gabor
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It makes no difference Gordon. Autorotation in Helis or flying Helis or flying fixwing or gyros are the same exact thing. Autorotation is flying.
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A walk in the woods helps me relax and release tension. The fact that I am dragging a body should be entirely irrelevant! A simple thank you would have been enough for the morning coffee without all that "how did you get in here" nonsense.
Jeff- Let me try one more time....but this is my last attempt.. A phone call is so much easier!
Of course gliding into the wind will bring your touch down point closer to you.
Birdy is talking about a headwind that decreases with altitude like most wind gradients have them do.
You are now going to have a shallower glide slope as you near the ground and you will start overshooting your landing spot.
It couldn't be more simpler
We are NOT saying you will glide farther into a headwind than you will with a tailwind...of course you wont glide as far into a headwind....
But......you will start gliding farther as that headwind gets smaller as you approach the ground.
We have agreement then. I understand completely and I cleared that up right at the beginning. If the headwind or tailwind increases or decreases for any reason, everything changes, obviously! And yes maybe poorly stated, but really that's what it sounds like if you read his statement. His statement reads as if one will land further into a headwind than with a following tailwind. I was not the only one confused by his statement. An experienced flyer like Muz was as well. Much easier to just say that the pilot should be wary of gradient changes as he gets closer to the ground, as the headwind or tailwind may be stronger or weaker than previously anticipated. Simple.
Last edited by loftus on Tue Feb 10, 2015 6:18 pm, edited 1 time in total.
Tue Feb 10, 2015 6:00 pm
Gabor
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The statement was: When your engine stops and you are going to do your engine out routine that you have practiced, with head winds introduced you will overshoot your target. And that is 100% true.
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A walk in the woods helps me relax and release tension. The fact that I am dragging a body should be entirely irrelevant! A simple thank you would have been enough for the morning coffee without all that "how did you get in here" nonsense.
Tue Feb 10, 2015 6:14 pm
Gabor
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Now let's talk about crack whores because this horse is fucking dead!
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A walk in the woods helps me relax and release tension. The fact that I am dragging a body should be entirely irrelevant! A simple thank you would have been enough for the morning coffee without all that "how did you get in here" nonsense.
The statement was: When your engine stops and you are going to do your engine out routine that you have practiced, with head winds introduced you will overshoot your target. And that is 100% true.
I guess the only way to prove this wrong is to go out to the airfield and land both ways down the runway starting from the same height and keeping the same glide speed. I am certain I will land further down the runway with zero wind or a tailwind, than I will into a strong headwind. As I said if I am wrong I will certainly give up flying, because my understanding of physics is wrong. But yes the point is it's about the gradients! So it's about a headwind becoming less of a headwind, i.e. more like a tailwind that will cause you to overshoot and visa versa. Now it's beaten and fully clarified in my mind at least. It's not about whether it's a headwind or a tailwind per se, but about gradients and changes in those winds as one gets closer to the ground. So now I think Birdy is right and Gabor is wrong.
Last edited by loftus on Tue Feb 10, 2015 6:33 pm, edited 5 times in total.
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