Improved shear/stall-spin alarms

I just wondering if current technology could provide improved stall-spin warnings/information.

For example, suppose you installed a pitot at each wingtip (and I'm making an assumption you need this level of resolution) and had an instrument that monitored/stored wingtip airspeed and fluctuations … and had inertial inputs that could provide information about how cleanly you were flying the ship.

This data would be evaluated relative to a flight envelope (algorithm and envelope would have to be developed)– and if you were near the envelope boundaries – because of atmospheric conditions (gusts or shear) … or how you were flying the ship (slipping or skidding) … or if you were close to the ground/terrain … alerts would display/sound. (Could this be a feature of our modern varios.)

Or do we consistently fly too close (or over) an envelope edge to allow this to work in practice.

KK

On Sunday, June 9, 2013 6:55:36 AM UTC-6, KiloKilo wrote:
I just wondering if current technology could provide improved stall-spin warnings/information.



For example, suppose you installed a pitot at each wingtip (and I'm making an assumption you need this level of resolution) and had an instrument that monitored/stored wingtip airspeed and fluctuations … and had inertial inputs that could provide information about how cleanly you were flying the ship.



This data would be evaluated relative to a flight envelope (algorithm and envelope would have to be developed)– and if you were near the envelope boundaries – because of atmospheric conditions (gusts or shear) … or how you were flying the ship (slipping or skidding) … or if you were close to the ground/terrain … alerts would display/sound. (Could this be a feature of our modern varios.)



Or do we consistently fly too close (or over) an envelope edge to allow this to work in practice.



KK

The key variable to monitor is angle of attack. Other than in the landing flare, there is no reason or need to operate a glider at an angle of attack greater than that for minimum sink. There's a fairly wide angle of attack range between min sink and stall where a slow/stall warning could be set so it isn't overly intrusive.

The Angle of attack probe itself can be just two pressure ports in the nose..

The warning itself could be lights, sounds or my preference, a stick vibrator like the ones in cell phones. Since most gliders have glide computers with AGL altitude, the warnings could be more insistent when low.

Technology is a wonderful thing and, given the time and money, we engineers
can develop anything you desire.

BUT... Would another bell or whistle really improve safety over simply
learning to fly correctly? Have we become so insulated from our
surroundings that we can't recognize a burble in the controls,a slacking of
pressure, a reduction in air noise?

In the 80s it was temperature probes on the wingtips in the hope that
detecting a slightly different temperature would have us turning into warmer
(rising?) air.

As was said earlier, it's AoA that you're looking for. They've already got
it; for civilian aircraft, too. Look he
http://www.aircraftspruce.com/menus/...ndicators.html


"Bill D" wrote in message
...
On Sunday, June 9, 2013 6:55:36 AM UTC-6, KiloKilo wrote:
I just wondering if current technology could provide improved stall-spin
warnings/information.



For example, suppose you installed a pitot at each wingtip (and I'm making
an assumption you need this level of resolution) and had an instrument
that monitored/stored wingtip airspeed and fluctuations … and had inertial
inputs that could provide information about how cleanly you were flying
the ship.



This data would be evaluated relative to a flight envelope (algorithm and
envelope would have to be developed)– and if you were near the envelope
boundaries – because of atmospheric conditions (gusts or shear) … or how
you were flying the ship (slipping or skidding) … or if you were close to
the ground/terrain … alerts would display/sound. (Could this be a feature
of our modern varios.)



Or do we consistently fly too close (or over) an envelope edge to allow
this to work in practice.



KK

The key variable to monitor is angle of attack. Other than in the landing
flare, there is no reason or need to operate a glider at an angle of attack
greater than that for minimum sink. There's a fairly wide angle of attack
range between min sink and stall where a slow/stall warning could be set so
it isn't overly intrusive.

The Angle of attack probe itself can be just two pressure ports in the nose.

The warning itself could be lights, sounds or my preference, a stick
vibrator like the ones in cell phones. Since most gliders have glide
computers with AGL altitude, the warnings could be more insistent when low.

On Sunday, June 9, 2013 9:19:11 AM UTC-6, Dan Marotta wrote:
Technology is a wonderful thing and, given the time and money, we engineers can develop anything you desire.

BUT... Would another bell or whistle really improve safety over simply learning to fly correctly? Have we become so insulated from our surroundings that we can't recognize a burble in the controls,a slacking of pressure, a reduction in air noise?

___________________

Some form of AoA sensing/stall warning is installed on every aircraft made - except rotorcraft and gliders. The sling-wing guys have an excuse, we don't. I think our terrible safety record speaks volumes.

Clearly, pilots don't universally recognize impending stall/spins. We've been trying to get them to do so for the entire history of flight without much success. It time for another solution now that we have the technology.

Bill D wrote, On 6/9/2013 9:04 AM:
On Sunday, June 9, 2013 9:19:11 AM UTC-6, Dan Marotta wrote:
Technology is a wonderful thing and, given the time and money, we
engineers can develop anything you desire.

BUT... Would another bell or whistle really improve safety over
simply learning to fly correctly? Have we become so insulated from
our surroundings that we can't recognize a burble in the controls,a
slacking of pressure, a reduction in air noise?

___________________

Some form of AoA sensing/stall warning is installed on every aircraft
made - except rotorcraft and gliders. The sling-wing guys have an
excuse, we don't. I think our terrible safety record speaks
volumes.

Clearly, pilots don't universally recognize impending stall/spins.
We've been trying to get them to do so for the entire history of
flight without much success. It time for another solution now that
we have the technology.

Has anyone tried any of various AOA instruments on the market? There are
several under $1000.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)
- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarm
http://tinyurl.com/yb3xywl

On Sunday, June 9, 2013 2:57:47 PM UTC-6, Eric Greenwell wrote:
Bill D wrote, On 6/9/2013 9:04 AM:

On Sunday, June 9, 2013 9:19:11 AM UTC-6, Dan Marotta wrote:

Technology is a wonderful thing and, given the time and money, we

engineers can develop anything you desire.



BUT... Would another bell or whistle really improve safety over

simply learning to fly correctly? Have we become so insulated from

our surroundings that we can't recognize a burble in the controls,a

slacking of pressure, a reduction in air noise?



___________________



Some form of AoA sensing/stall warning is installed on every aircraft

made - except rotorcraft and gliders. The sling-wing guys have an

excuse, we don't. I think our terrible safety record speaks

volumes.



Clearly, pilots don't universally recognize impending stall/spins.

We've been trying to get them to do so for the entire history of

flight without much success. It time for another solution now that

we have the technology.



Has anyone tried any of various AOA instruments on the market? There are

several under $1000.



--

Eric Greenwell - Washington State, USA (change ".netto" to ".us" to

email me)

- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarm

http://tinyurl.com/yb3xywl

I don't know if there is one designed from the beginning as a glider instrument. Here's what I have in mind:
http://www.technology-market.eu/part...84FB_3IDG.html

Except, there's no need for a separate probe, just use the glider's nose as a probe's nose cone and add the pressure sensing ports.

At 16:04 09 June 2013, Bill D wrote:
On Sunday, June 9, 2013 9:19:11 AM UTC-6, Dan Marotta wrote:
Technology is a wonderful thing and, given the time and money, we
engineers can develop anything you desire.

BUT... Would another bell or whistle really improve safety over simply
learning to fly correctly? Have we become so insulated from our
surroundings that we can't recognize a burble in the controls,a slacking
of
pressure, a reduction in air noise?

___________________

Some form of AoA sensing/stall warning is installed on every aircraft
made
- except rotorcraft and gliders. The sling-wing guys have an excuse, we
don't. I think our terrible safety record speaks volumes.

Clearly, pilots don't universally recognize impending stall/spins. We've
been trying to get them to do so for the entire history of flight without
much success. It time for another solution now that we have the
technology.

Why don't they? If they are properly trained they should. If they are
regularly checked they should.
A lot more time is spent, IMHO too much time, teaching the recovery from a
stall/spin and far too little time is making sure that people do really
recognise the signs of an approaching stall. Knowing the recovery from a
stall and being super reactive in applying corrective action for a fully
developed spin in the final turn is more likely to kill you that letting
the spin continue. Recognising the signs of an approaching stall and taking
the corrective action will save you every time. Recognising the signs of an
approaching stall is not difficult so why do people get caught out.
The problem with replacing skill and good practice with technology is that
people come to rely on the technology and when it fails are completely
screwed.
As a very experienced airline pilot put it. Automatic take off, automatic
flying and automatic landing = automatic crash.

On Sunday, June 9, 2013 12:04:54 PM UTC-4, Bill D wrote:


Some form of AoA sensing/stall warning is installed on every aircraft made - except rotorcraft and gliders.

Do many pilots recount hearing the stall alarm on the turn to final and then saving their own butt? Or are stall alarms only effective when they go off high above the ground?

On Sunday, June 9, 2013 9:27:16 PM UTC-6, son_of_flubber wrote:
On Sunday, June 9, 2013 12:04:54 PM UTC-4, Bill D wrote:





Some form of AoA sensing/stall warning is installed on every aircraft made - except rotorcraft and gliders.



Do many pilots recount hearing the stall alarm on the turn to final and then saving their own butt? Or are stall alarms only effective when they go off high above the ground?

Most definitely! Low altitude is where they save your butt.

I've found stall horns annoying in high performance flying. It's the
physical signals the airplane gives, not alarms, that tell me a stall is
imminent. You should really learn to feel the aircraft and not rely on
horns, bells, whistles, gauges, etc. They WILL fail some day...


"Bill D" wrote in message
...
On Sunday, June 9, 2013 9:27:16 PM UTC-6, son_of_flubber wrote:
On Sunday, June 9, 2013 12:04:54 PM UTC-4, Bill D wrote:





Some form of AoA sensing/stall warning is installed on every aircraft
made - except rotorcraft and gliders.



Do many pilots recount hearing the stall alarm on the turn to final and
then saving their own butt? Or are stall alarms only effective when they
go off high above the ground?

Most definitely! Low altitude is where they save your butt.