Primarily for general aviation discussion, but other aviation topics are also welcome.
#1838189
I can’t see the point in having a speed limiting filter/setting at all. Is this just another setting to fiddle with?
If the target turns out to be unmoving, in a house, Shirley it’s not much of a threat?
#1838195
I think this is no problem. Any pilot with half a brain should recognise that if they are at 300 ft on final (or climb out) and get an alert of an aircraft 300 ft below - that there is a 99.999 % probability that some aircraft on the ground has switched on their transponder. One would take a look and monitor the altitude difference to assess whether it is becoming a threat. No problem in my view.
Rob P, gaznav liked this
#1838196
Crash one wrote:I can’t see the point in having a speed limiting filter/setting at all. Is this just another setting to fiddle with?
If the target turns out to be unmoving, in a house, Shirley it’s not much of a threat?


"Aircraft ahead 12 o'clock 1,000ft below"

Glance at altimeter, I am at 1,000ft (give or take). Disregard.

Only if you are getting closer and the vertical separation is decreasing do you bother awarding it much attention.

Rob P

*Simultaneous post with @Lefty ^^^^
#1838201
From reading the OP description it sounds to me like there was an aircraft on the ground transmitting its position in some way, without saying “I’m on the ground” which would have caused SkyDemon to ignore it.

Once the OP was barrelling down the runway towards that other aircraft, SkyDemon decided it presented a threat and warned about it.

Speculation of course.
gaznav liked this
#1838204
Crash one wrote:I can’t see the point in having a speed limiting filter/setting at all. Is this just another setting to fiddle with?
If the target turns out to be unmoving, in a house, Shirley it’s not much of a threat?

The problem is that if you get too many false warnings (or rather warnings that aren't meaningful) one tends to start ignoring them.
#1838224
malcolmfrost wrote:
Crash one wrote:I can’t see the point in having a speed limiting filter/setting at all. Is this just another setting to fiddle with?
If the target turns out to be unmoving, in a house, Shirley it’s not much of a threat?

The problem is that if you get too many false warnings (or rather warnings that aren't meaningful) one tends to start ignoring them.


That’s what the human brain is for, to make decisions based on information.
If it’s too much trouble, switch the thing off and open the eyes!
#1838258
@Crash one Re-read Boeing Boy's original post. If an experienced pilot such as he can be distracted then an issue exists.

There's no 'fiddling' involved with setting up an 'air switch'; it's just a simple matter of telling the machine what you consider to be your aircraft's parameters for being airbourne. You set it, save it and then forget about it. What that prevents is people like Boeing Boy having the s**t scared out of him just as he takes to the air and THEN having to diagnose the problem.

Your simplistic view of the solution is not at all helpful and fails to take into account any of the human factors involved in a situation that distracts and requires immediate diagnosis due to the urgency level of the warning. A patronising reply of 'look out the window' does nothing to solve the very real problem.

What it does need is for people to read their instruction books, understand their equipment and set the air switches. For those using extended squitters in Mode S transponders that don't have an air switch, turn the poxy things to standby once off the runway.
malcolmfrost, Dusty_B liked this
#1838279
Avianca 011 1983. In those days GPWS was unreliable and could generate false warnings.
The accident was investigated by the Spanish Accident Investigation Board, who determined the most likely cause to have been pilot error, and a failure to follow proper instrument approach procedures. The pilot was not precisely aware of his position, and the Board determined he had "set out to intercept the ILS on an incorrect track", which placed the aircraft over the wrong terrain for his approach, in a hilly region of rapidly changing terrain height. [3]

The crew also did not respond properly to the ground-proximity warning system (GPWS), which can be heard on the flight recording. (There is a persistent rumor that the pilot responded to the GPWS by saying "Shut up, Gringo" but this is not borne out by the transcript of the recording; the pilot responds to 15 seconds of GPWS warning with "Bueno, beuno", roughly, "Ok, ok" in English.[4][5])
#1838308
PaulSS wrote:@Crash one Re-read Boeing Boy's original post. If an experienced pilot such as he can be distracted then an issue exists.

There's no 'fiddling' involved with setting up an 'air switch'; it's just a simple matter of telling the machine what you consider to be your aircraft's parameters for being airbourne. You set it, save it and then forget about it. What that prevents is people like Boeing Boy having the s**t scared out of him just as he takes to the air and THEN having to diagnose the problem.

Your simplistic view of the solution is not at all helpful and fails to take into account any of the human factors involved in a situation that distracts and requires immediate diagnosis due to the urgency level of the warning. A patronising reply of 'look out the window' does nothing to solve the very real problem.

What it does need is for people to read their instruction books, understand their equipment and set the air switches. For those using extended squitters in Mode S transponders that don't have an air switch, turn the poxy things to standby once off the runway.



I’m not trying to be patronising.
Looking outside is not being simplistic, it’s a necessity.
If people are being dangerously distracted by their EC devices then yes there is an issue and blaming idiots for leaving transponders on isn’t the solution unless you can educate them!
Rather than set a speed of your own aircraft, why not program the device to warn if the distance is decreasing but not warn otherwise, and set the warning distance to less than a mile or what you feel safe with? Or better, set the collision time in seconds! Flarm prob does something like that.
#1838320
Rather than set a speed of your own aircraft
........all that setting a speed does is to tell your ADSB when to start transmitting. We want people to do that, instead of it blaring all the time and causing unnecessary warnings

why not program the device to warn if the distance is decreasing but not warn otherwise
............clearly that set up would have resulted in the same situation in Boeing Boy's case but, in the wider context, restricting the kit to such narrow parameters reduces the ability to build up a bigger picture of what's going on around you. For instance, yesterday I saw (on my SkyDemon, provided for by my PilotAware) an RV in a big left turn off to my front right hand side. I was able to consider the fact that his big turn was going to result in him coming at me in about 250 degrees more turning and, so, manoeuvred to my left a bit to increase the separation. With your suggestion I would have received a warning about him much later and MAY have had to take some fairly evasive manoeuvre. In the event, thanks to the bigger air picture, I was able to avoid any of that nonsense and keep Mrs SS far less jittery than she would have been with a red warning and a largish turn.

........and set the warning distance to less than a mile or what you feel safe with?
......you can already do that.

Or better, set the collision time in seconds!
..........How would that have worked in the example above? The RV was only inbound to me during the last 20 degrees or so of his turn, so it would have been a very late warning. I could have set it to warn me of traffic within 2 minutes but that wouldn't have made any difference in this case to the lateness of the warning I would have received. TCAS uses closest point of approach but, I suggest, this is much more useful in the CAT world where most of the time you're flying in a straight line and any turns etc are quite leisurely.

All the facilities are there for Boeing Boy not to have received such a warning but too many out there are either ignorant of these facilities, too lazy to set them up or need educating in operating as if they're not the only people on the planet. Just ensure you're not transmitting when on the ground; it's that simple. Be that an air switch (physical or set in the software somehow) or only operating the Mode S transponder (whether using an extended squitter or not) once lining up on the runway and turning it off when vacating, it takes almost no effort to allow BB to retain some of his heartbeats.
#1838327
I would agree you can’t set a distance/time warning for a threat in a turn.
It’s not possible to envisage every scenario so that’s where your brain did the job.
Compulsory squat switches? Flap operated switches? Or a thick ear after the event!
Let’s not fight over it, it is an issue.
#1838392
I really am at a loss to see what your point is, Crash one.

If we went with your suggestion of time I wouldn't have received the information for my brain to do its job. If we went with the trite phrase of 'look outside' there's a good chance I wouldn't have seen the RV until the last second.....if I saw him at all (and I have a pretty good idea of how to search for target aircraft visually).

I don't really understand you questioning of how to ensure the equipment is operated properly. Certainly a squat switch (physical) is one way of doing it, as I have previously suggested. Flap operated is not so good because (a)not all aircraft have flaps and (b)flaps up would be the trigger to operate the device, which means you'd have to have the flaps out of up whilst on the ground in order to turn it off. Alright in an RV but not most other aircraft, where flaps are normally retracted on the ground.

I agree it is an issue but I don't really think you understand it fully if you believe people are twiddling with settings, getting distracted and should turn their units off a look outside instead. The issue is why their EC units are distracting them by providing false warnings and it's not the 'warnings' that needs addressing but the 'false'. Turning off the units doesn't solve that problem but stopping people transmitting when they're on the ground will. I didn't suggest a 'thick ear'; I suggested education and people better understanding the equipment they're using.
#1838397
I have agreed there is an issue with distraction, I don’t have the answer. I can’t see the value in speed settings.
I’m only chucking ideas about in case some other solution is out there.
#1838414
@Crash one
I can’t see the value in speed settings.


The speed settings are purely there to act as an air switch and tell SE2 etc to start transmitting. Without the air switch, or without it set up properly, the unit will transmit whilst the aircraft is on the ground and electrical power applied. This leads to false and nuisance warnings of the type received by BB.

SkyEcho already has one of the answers to the problem. It’s not the equipment that’s the problem but the failure by some to configure it correctly. Of course, this is not just a SE2 problem and those who do similar with their transponders etc are just as guilty of providing nuisance warnings when they’re on the ground.

Maybe the equipment (not just SE2) manufacturers could allow transmissions for testing purposes only when speed is, for instance, 10 kts or less. Above 10 kts the air switch speed would have to be configured or else it would remain in receive only. Helicopters would be the obvious exception but the 10 kt ‘rule’ could be overidden by a helicopter setting, perhaps tied in with the HEX setting. This is, however, a HUGE hammer to crack a nut and could far more easily be solved by people just reading the instructions and/or understanding when they’re transmitting.