Engine failure turn back.

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Hephaestus

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I've wondered how long it will be before we read of an accident involving a pilot known to have a habit of flying through the Rocks in IFR using his synthetic vision. Knowing that GPS satellite signals can be blocked by surrounding peaks, I sure wouldn't attempt it. Someone surely will.
Oh it'll probably happen, may already have - surprisingly in the rogers corridor, I've been pretty rock solid for GPS signal... Crowsnest is a different story.
 

Daleandee

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I've wondered how long it will be before we read of an accident involving a pilot known to have a habit of flying through the Rocks in IFR using his synthetic vision. Knowing that GPS satellite signals can be blocked by surrounding peaks, I sure wouldn't attempt it. Someone surely will.
This isn't the exact scenario you speak of but this video does show what I consider to be some really unwise decision making:

 

Dan Thomas

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Oh it'll probably happen, may already have - surprisingly in the rogers corridor, I've been pretty rock solid for GPS signal... Crowsnest is a different story.
Pre-GPS, I've been through the Rogers at lower level due to ceilings. I'm sure a GPS would have been unreliable then.
 

Hephaestus

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Pre-GPS, I've been through the Rogers at lower level due to ceilings. I'm sure a GPS would have been unreliable then.
When I was doing it in the cherokee 140 - that's all I could do - engine saying "i think i can i think i can" all the way through. I really don't miss those days, still largely transit along tch because that's the route I'm most comfortable on - just a little higher now 😆
 

Aesquire

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A variometer is a VSI with a small weighted piston in a cylinder that detects vertical accelerations and pushes or pulls air into or out of the VSI bellows to make it react faster.
I've never seen one like that, which means very little, since none I've used had a bellows at all. Neat idea, in theory. But a Variometer with airspeed input for Total Energy Compensation was the gold standard before GPS.


Actually, now that I think, the old one I was told to ignore in that club 2-33 might have had a bellows. I still have one with pith balls in my closet, which Worked really well, albeit without audio. Everything else, from Ball s to tiny ones on a circuit board the size of the 9 volt battery were electric. ( the tiny ones are now coin sized, half for speaker size ( audio only ) and half so you don't lose it. )

I'll ignore modern varios with GPS and full flight computer thermal mapping and landing dot on map than moves with airspeed and wind direction. Also engine instruments.

Re: the Impossible Turn.

It's good learning and quite fun to practice engine idle ( for safety ) steep turns with your eyes out of the cockpit, with plenty of altitude. Repeat with split attention on airspeed and/or AOA readings, but your purpose is to develop the Conditioned Response/sensory & muscle memory with eyes on the outside world.

As to speeds to fly, min sink speed gives you time to think, while flying straight and level, descending. But is a horrible idea while maneuvering. Times that min sink speed is smart are limited, mostly at higher altitudes than the engine failure on take off gives. So... Don't.

Best glide speed, Plus, is best. That's the cushion you've got, the speed over best glide, to stretch the glide. And the concept of "stretching your glide" should be accompanied by disbelief and pessimism. You can ONLY do that if you're well above max L/D, or by speeding up If you're at min sink, which is psychologically difficult.

Imho there's a tendency to want to slow down as the ground approaches and relative angles/motion give you the speed rush.
 

964SS

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Interesting discussion with many different views. However, the “average pilot” doesn’t doesn’t dive this deep into theory. Most are the kick the tires and light the fires type. So I continue to teach either straight ahead, or at most a 90 degree turn L or R. Land on a taxiway, open field, or pick the softest thing to hit while flying it all the way in.
 

tallank

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It does not. I was a commercial pilot and an instructor. Have an IFR rating. Taught Aircraft Systems in college. It takes a few seconds at most. Taking minutes would make it completely useless.

A variometer is a VSI with a small weighted piston in a cylinder that detects vertical accelerations and pushes or pulls air into or out of the VSI bellows to make it react faster.

Airspeed indications change very quickly. The principles of operation of the ASI and VSI are different.
The Rate of Climb is useless for short term changes. You will see this if you ever tried to fly by the Rate of Climb rather than only referencing it occasionally. Again, you can see this when you first takeoff. You will see that it slowly climbs as time goes by. It does not show the same number right after liftoff as it does a couple of minutes later.

Sorry but you have no idea how a variometer works. I have built a couple of them and flew sailplanes for 25 years. The rate of climb is measured by sensing the amount of air that is flowing in and out of container of air as the pressure changes due to altitude changes. The Veriometer has a big air bottle (a thermos) compared to a Rate of Climb just has its small case The viriometer is more sensitive to the change in air pressure do to altitude changes. One of the instruments I built would sense one foot change in altitude. There is no piston involved. How would you eliminate what turbulence would do to it?
 

Dan Thomas

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Interesting discussion with many different views. However, the “average pilot” doesn’t doesn’t dive this deep into theory. Most are the kick the tires and light the fires type. So I continue to teach either straight ahead, or at most a 90 degree turn L or R. Land on a taxiway, open field, or pick the softest thing to hit while flying it all the way in.
AS an instructor I realized that it was better to be a little high on a forced approach than a little low. It's better to bang into something at rolling speed that to hit something at flying speed.

We did a lot of off-airport work. New students who came with a PPL were sometimes shocked when we asked them to land in the grass alongside the runway. "You can do that??" they asked. We had access to some short, primitive farm strips, and deserted gravel roads too. We got the students used to the idea of taking the handiest bit of ground available.
 

Dan Thomas

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One of the instruments I built would sense one foot change in altitude. There is no piston involved. How would you eliminate what turbulence would do to it?
1620401078555.png

What is your aircraft systems experience and qualifiactions? If your VSI takes minutes to settle down, it's defective and useless.
 

Aesquire

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I totally agree that if your VSI takes more than a few seconds to give you some reading, the actual number is less important, it's junk.

The ancient instrument shown in the illustration above is fine if there's no electricity, but no glider pilot would waste panel space for it from the 1970's onward. I wouldn't bother to glance at one today, but I would have bought one back in 1976.

I've spent hours with a pellet type, with a lunch box thermos strapped up in the wing ( double surface hang glider ) and the indicator velcroed to a foam wedge duct taped to the control bar ( to keep it more or less level ) Mine was smaller & lighter than this one.
Cosim Variometer.jpg

And the newer little ones... ( I've seen smaller ) SkyBean 2 - mini audio variometer for Paragliding and Hang Gliding | eBay
 

Pops

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On my homemade autopilot to lock on a pressure altitude, I used a quart glass jar. Would hold altitude within 25 feet. Set the gain up more and it would start oscillating in pitch. 25 feet was close enough for me.
 

964SS

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AS an instructor I realized that it was better to be a little high on a forced approach than a little low. It's better to bang into something at rolling speed that to hit something at flying speed.

We did a lot of off-airport work. New students who came with a PPL were sometimes shocked when we asked them to land in the grass alongside the runway. "You can do that??" they asked. We had access to some short, primitive farm strips, and deserted gravel roads too. We got the students used to the idea of taking the handiest bit of ground available.
I love it when they ask that. Lol
 

Dan Thomas

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I do not understand what the piston does. Once established on your climb there is no acceleration. Where did you get your picture?
It's an IVSI that was often referred to as a variometer and was used in gliders in the 1970s when I was towing them. A VSI needs a changing static pressure to start reading and it takes a few seconds to stabilize at an accurate rate. For gliders that doesn't work so well with little thermals, so the piston reacts to any upward or downward acceleration and pumps air in or out of the bellows to move the needle instantly and the pilot knows what he's got. Once a steady climb or descent is established the piston recenters and by that time the IVSI bellows is operating normally. It's seamless and it works. Or worked, if newer stuff is electronic.

How Instantaneous Vertical Speed Indicators Combat Lag Time
 

tallank

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View attachment 110334

What is your aircraft systems experience and qualifiactions? If your VSI takes minutes to settle down, it's defective and useless.
I did find a reference to the VSI delay. It said 9 seconds. So I do think my two minute delay is not correct. Was told that in my gliders days many decades ago. A 9 second time constance would mean that it reach 70% of the actual rate of climb after 9 seconds.
 

Dan Thomas

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I did find a reference to the VSI delay. It said 9 seconds. So I do think my two minute delay is not correct. Was told that in my gliders days many decades ago. A 9 second time constance would mean that it reach 70% of the actual rate of climb after 9 seconds.
Six to nine seconds to catch up. I never encountered any VSI that took 9 seconds. I used to do pitot-static leak tests and had to watch the VSI to avoid pegging it while increasing or decreasing system pressure. The VSIs responded rather well. And for NDB or VOR IFR approaches you had to establish, quickly, a specific descent rate or you'd be in trouble. A slow VSI is a dangerous VSI. If the static lines have a blockage it would be slow. If the calibrated orifice is partially blocked it will overread in either direction.
 
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