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Modern AOA disappointmentad


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10 minutes ago, gsengle said:

The fact is, using aoa is a primary measurement for stall, and always works if measured accurately. Using IAS, adding weight, density altitude, bank angle, and hoping your airplane matches the test airplane is using a calculated derived number... In truth you could get rid of airspeed and fly only aoa...

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IDK, your theory tugs at the heart strings, but the airlines seems be killing people at 1/50th of the rate of GA and in some years, kill Zero.  Factor that 

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Because they only fly very very safe profiles, limit bank angles, always fly ILS to long runways. That's the safety margin. Well if you want to have to fly your Mooney only like a bus, and stay on 5000+ foot runways, then go for it.

And modern airliners have envelope protection, driven by, guess what, aoa.

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3 minutes ago, gsengle said:

 

Because they only fly very very safe profiles, limit bank angles, always fly ILS to long runways. That's the safety margin. Well if you want to have to fly your Mooney only like a bus, and stay on 5000+ foot runways, then go for it.

And modern airliners have envelope protection, driven by, guess what, aoa.

 

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Google the 737, the 747 the 737-400, you can stall it, no stick pusher, no envelope protection.  If you want to, you can do a barrel roll.   If you're speaking from experience lets hear it, but otherwise its just speculation. And  guess you forgot the part where  routinely land and stop in 800', and regularly and on grass. Let me ask this, whens the last tie you landed on a 2500' grass runway? 

The maneuvering speeds placarded in the FMC give you 45 degrees of bank for stall protection. And yes it depends on weight but not as much as you think. I dont have an FMC in the 201 but I do know that 100 MPH IAS will protect you to 2G, which much more than 45 degrees of bank in a level turn. 90 MPH is good to 45 degrees, and 30 degrees is lower than that.  At some point you havre to own the fact that you have to fly the airplane, and any shortcoming of that is due to the PIC.   Gadgets may assist but in the end, its man and machine. 

Edited by jetdriven
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It's not a gadget, it's a primary measurement of how well the wing is doing. You're just being old fashioned. Bet you would have argued for wing warping too. Let's ditch the airspeed indicator.... Lol

Ps don't mischaracterize what I said. I said MODERN airplanes have envelope protection.

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Just now, gsengle said:

 

It's not a gadget, it's a primary measurement of how well the wing is doing. You're just being old fashioned. Bet you would have argued for wing warping too. Let's ditch the airspeed indicator.... Lol

Ps don't mischaracterize what I said. I said MODERN airplanes have envelope protection.

 

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Then why is it required to be placarded as not primary flight info only, just for advisory info only?  Explain that

 

Yes the 737 is not a modern airplane. But do this, show me one transport category jet that has an AOA indicator.  ONE> 

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Google makes it too easy.

"A dedicated AOA indicator shown on the primary flight display (PFD) recently has been developed in cooperation with airline customers. The new indicator is offered as an option on the 737-600/-700/-800/-900, 767-400, and 777 at this time."

http://www.boeing.com/commercial/aeromagazine/aero_12/attack_story.html

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 the 737 has this unit too/ It feeds the ADC, but its only for stall shaker protection, and the computed speeds vs weight are what we fly. How many times has the sick shaker activated while I'm a crew member? zero in 8000 hours.  Not that it can't happen, but just that it hasn't. 

9 hours ago, gsengle said:

Google makes it too easy.

"A dedicated AOA indicator shown on the primary flight display (PFD) recently has been developed in cooperation with airline customers. The new indicator is offered as an option on the 737-600/-700/-800/-900, 767-400, and 777 at this time."

http://www.boeing.com/commercial/aeromagazine/aero_12/attack_story.html

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Rant deleted 

Edited by jetdriven
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1 hour ago, jetdriven said:

I do that too, with no AOA and and varying weights, too You know Boeing airplanes have the weight in the FMC and put a VREF speed for the weight. it works. Landing speed varies with weight, I get that, but as Don Kaye says you can calculate that.  

 

its about 71 MPH over the numbers at minimum landing weight and, as Hank said, add 1 knot per 300 lbs.  But you dont need an airspeed indicator in a 747-400 and you dont need one in a M20J. You simply fly the speed that gives you a 2 degree nose up attitude on final. Particularly short final.  The -400 is 2.5 to 3 degrees ANU, but its the same concept.  if the airplane starts to sink you're too slow.  If you got to scooch up in the seat to lift up and see the runway numbers on final, you're too slow. if you are pointed at the runway you're too fast. nose down too fast. 100 MPH too fast.  If you're in doubt, you're too fast.  This isn't hard stuff. The 1900, the CRJ, the 747-200, the 747-400, the Aribus A320, all variants of the 737, the 727, the 757, 767,  none had an AOA gauge.  They all have AOA vanes to set off the stick shaker, but the VREF was calculated by weight and seems to work.  

 

I'm an engineer and so I'm pretty good with numbers.  But why bother. I can also shoot an approach with and ADF, but who wants to when the 540W and the Stec30 will do it for me. Meanwhile I watch and make sure they done screw it up. Why do all the math, with the possibility of human error when the little blinky lights make it so easy.  It is the 21st century after all.

1 hour ago, jetdriven said:

your system uses a stall vane which moves up and down. But it doesn't measure AOA directly.  How accurate is it with flaps up, 15 degrees, or full down? What about with ice on it?

I don't fly in ice! And if I was ever iced up, the AOA is the least of my worries. And I'm certainly not relying on it to get me into a short strip or monitor a tight base to final turn.

I don't need the AOA or the ASI or anything but my butt in the seat to properly land on a 6000+ ft runway. I'm not a professional pilot, and don't have a copilot either.  So I'll take the little AOA vane, in spite of the fact the FAA hasn't had the resources to certify it as a primary instrument, and be thankful for the help.

Speaking of professional pilots, there are plenty I wouldn't let fly my Mooney no matter how many 73?? whatever's they have time in. 

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where is the AOA indicator, private pilot?  an AOA sensor is not thing, the cockpit display is another. But a professional pilot would know that, a hobbyist, not so much. Read and learn you can aspire to greatness someday Until then, kiss your wife every time you leave. 

 

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You're just a jerk, I know the difference between an indicator and a sensor. The fact is the input is there. And I expect better than insults from a so called professional. But I guess my physics degree makes me less qualified to discuss airplane design than a driver. Good night.

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12 minutes ago, jetdriven said:

Then you can't read then, even with al that physics training.  Im married to an engineer and I can attest they can grasp the concepts but you aren't that person. 3D is hard for some folks. You should buy a cirrus with the "straight and level button" its even blue to identify more easily. 

 I said show me an AOA indicator for a modern commercial jet, you show an AOA vane. Nice Kings X, you win, right?  ok, yeah.   The 737 has an AOA bt no envelope protection, yet the accident rates are similar. But airline pilots dont fly AOA they fly airspeed based on weight, but if you were a professional pilot you would know that but instead you want to give a flying lesson. Theres a reason GA is 50X more fatal than airlines, it isn't the aircraft, since 135 flies the same airplanes we do.  Its the mentality and the knowledge of the nut behind the yoke. Ask Pierre Bonin, FO of AF447, well, never mind, he's dead. Along with his whole crew and passengers. Attitude plus power = performance never crossed his mind. All the gadgets were lying to him.  FTFA never came up.  But some thing enough gadgets can fly the plane for them. Or at lest keep them out of trouble. Ask  Anyways, OK, partner, airlines are hiring, take your theoretical know it all knowldge and apply.  Tell them how it is.  

 

Byron, admit it, you like airspeed cause it's an easy value to punch into the autopilot to let the plane fly itself! :P

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42 minutes ago, gsengle said:

 

It's not a gadget, it's a primary measurement of how well the wing is doing. You're just being old fashioned. Bet you would have argued for wing warping too. Let's ditch the airspeed indicator.... Lol

Ps don't mischaracterize what I said. I said MODERN airplanes have envelope protection.

 

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Don't you know that if you like something you call it an instrument, and if you are trying to put it down, you call it a gadget or toy.

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Just now, DonMuncy said:

Don't you know that if you like something you call it an instrument, and if you are trying to put it down, you call it a gadget or toy.

Well the dentist's airplane is so fast that it can't stall!

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I bought the Alpha Systems "AOA" a couple of years ago to see if it was worth while.  I'd been teaching for 22 years at the time and, therefore, had done thousands of landings.  We took care in doing the calibration.  I found that even with my experience, I was able to shave pretty close to 5 knots off of my landings comfortably flying the blue donut (1.3Vso) and then on short final going to the upper half donut (1.2 Vso).  I have the Valkyrie HUD down during cruise and raise it on approach.  It's mounted on the glare shield so is in my line of sight all the time.  I'll set it up for the donut and then check the airspeed for reference, without doing the mental calculations I used to do before each landing to determine the appropriate speed.

Ron Blum from Mooney doesn't like the pressure differential "AOA".  Probably his reasoning is correct.  He's an aeronautical engineer. I'm not.  Mark Korin from Alpha Systems disagrees with him.  But in any event for 1g flight on approach that system works.  Lately, there has been a system update to the Alpha Systems AOA to a 4 point calibration.  This further corrects for non linearity.  I spoke to Mark about this last week at Oshkosh, and he said not to waste my time sending in the computer; that I wouldn't notice a difference.

Bottom line, I like the unit and find it useful even in the limited approach situation. Certainly you could do without it and make consistently good landings on fields you're used to, but go to higher DA fields on hot days with a forward CG, and it's nice to not have to look up the numbers on the fly.

Should you get one?  I'll leave that up to you.

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21 minutes ago, donkaye said:

I bought the Alpha Systems "AOA" a couple of years ago to see if it was worth while.  I'd been teaching for 22 years at the time and, therefore, had done thousands of landings.  We took care in doing the calibration.  I found that even with my experience, I was able to shave pretty close to 5 knots off of my landings comfortably flying the blue donut (1.3Vso) and then on short final going to the upper half donut (1.2 Vso).  I have the Valkyrie HUD down during cruise and raise it on approach.  It's mounted on the glare shield so is in my line of sight all the time.  I'll set it up for the donut and then check the airspeed for reference, without doing the mental calculations I used to do before each landing to determine the appropriate speed.

Ron Blum from Mooney doesn't like the pressure differential "AOA".  Probably his reasoning is correct.  He's an aeronautical engineer. I'm not.  Mark Korin from Alpha Systems disagrees with him.  But in any event for 1g flight on approach that system works.  Lately, there has been a system update to the Alpha Systems AOA to a 4 point calibration.  This further corrects for non linearity.  I spoke to Mark about this last week at Oshkosh, and he said not to waste my time sending in the computer; that I wouldn't notice a difference.

Bottom line, I like the unit and find it useful even in the limited approach situation. Certainly you could do without it and make consistently good landings on fields you're used to, but go to higher DA fields on hot days with a forward CG, and it's nice to not have to look up the numbers on the fly.

Should you get one?  I'll leave that up to you.

Respect.

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So I'll weigh in on this discussion at the risk of being ridiculed. But first a disclaimer....I'm a rank amateur pilot....I know and accept that flying is a hobby for me. At the same time, I try to stay informed and educate myself because I believe this enables me to be as safe a pilot as possible, given my time and financial constraints. 

I purchased and installed a CYA-100 instrument/gadget primarily to give myself an edge if/when I get into a situation where clear thinking might be hindered by blood flow to my brain because my sphincter muscle has contracted to the point I've got seat leather up my backside. ( My wife tells me on a regular basis my head must be up my derriere due to time and money spent on aviation)  I honestly don't understand how a wing can stall at any given airspeed.....but I trust those who have spent time studying aerodynamics. 

I like the fact I've got an audible and visual warning to supplement other instruments that might be difficult to decifer if I'm not thinking clearly. Push on the yoke and level the wings. With a stall wearing horn there's not a "range". The CYA has 10 led lights to give me a better idea of how close I am to a stall. If I get to the point I can fly with confidence to handle any situation maybe I'll pull it from the panel....but I'm sure that'll be in another lifetime. :) 

I also like the fact it helps with consistent approaches.......

 

 

 

 

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I'm curious, what do the big jets with AOA indicators look like?

There has been some conjecture that AOAs can save lives, got any data to back that up?

Lets take the turn to final, where the pilot realizes he is overshooting the runway, his head is turn to the left, a 100 AOA indicators glowing blue, yellow or red is not going to help him.

I have my speeds on by checklist, all for mid weight, I add or subtract if heavy or light, seems to work just fine, maybe if I was flying into sub 2000' runways I'd want more precision. Someday I might take a ride with someone who has a AOA and I'll change my mind, for now, they seem like secondary stall indicators.

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10 hours ago, gsengle said:

You're just a jerk, I know the difference between an indicator and a sensor. The fact is the input is there. And I expect better than insults from a so called professional. But I guess my physics degree makes me less qualified to discuss airplane design than a driver. Good night.

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I'm grateful that we have professional pilots here on MS who, despite the abuse, have the patience and take the time to share their expertise and their knowledge for the taking. They are an invaluable asset to the forum. 

While I can walk into a college physics class and teach it, I don't feel my physics degree qualifies me to dictate to a professional pilot on matters totally within his/her realm and out of mine!

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A wise man once told me never discuss politics and religion unless you want to cause conflict. 

Sooooooo.......leaving those touchy subjects aside....who else feels that Melania would be the no brainer choice instead of Hillary or Trump?

 

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