Tales of soaring software + device crashes, wrong or misleadinginformation presented, and user errors?

It would be useful to hear your tales of soaring software crashing and/or providing misleading or inaccurate information. Please be specific.

It would also be good to hear about cases of "user error" where you made a mistake in either setting up the device, misinterpreting the information displayed, or you found yourself confused or mislead by the way the information was presented. Of particular interest would be pitfalls that you stumbled upon in flight and how you resolved the difficulty.

I'd also like to hear about any cases of two devices running in parallel and presenting conflicting or diverging information (for example different indications of wind direction/speed or final glide arrival height).

On Thursday, May 30, 2013 9:03:40 AM UTC-7, son_of_flubber wrote:
It would be useful to hear your tales of soaring software crashing and/or providing misleading or inaccurate information. Please be specific. It would also be good to hear about cases of "user error" where you made a mistake in either setting up the device, misinterpreting the information displayed, or you found yourself confused or mislead by the way the information was presented. Of particular interest would be pitfalls that you stumbled upon in flight and how you resolved the difficulty. I'd also like to hear about any cases of two devices running in parallel and presenting conflicting or diverging information (for example different indications of wind direction/speed or final glide arrival height).

My gps source is a cambridge 302A. I run XCSoar 5.2.4 on an old iPAQ 3850. It is stone-axe reliable, and has the brightest in-sunlight display I've ever seen. I also have a Dell Streak, but the display is really nowhere near as good as the iPAQ. However.... the iPAQ won't run later versions of XCSoar gracefully.

Software Crashes and bugs:

I use XCSoar and I am a strong proponent of it, but I have had my share of crashes or bugs. Because of that, I'm glad to have backup loggers for OLC or Contest purposes. None of the crashes have required anything more than restarting XCSoar to recover from them. The biggest tragedy is the loss of a contiguous IGC file.

- Internal GPS on the Dell Streak isn't perfect. I've had XCSoar lose position info because of this. Not XCSoar's fault obviously. Connecting to a more reliable GPS like Flarm as the primary GPS source works great. When the Internal GPS does get wonky, you may just notice that your moving map isn't moving or updating.

Cambridge L-Nav/GPS-Nav: Remarkably stable. Only a few issues that have ever required a restart in the air. Wind data in straight flight isn't as trustworthy as I would like and switching between screens will show different arrival heights. That's me not remembering what those screens show for calcs. Not a software problem.


*** Software Limitations that produce less than reliable information: (Really Human failings to account for those limitations)

Bogus Wind:
GPS based software like See You Mobile , LK8000 or XCSoar all only understand the wind if you are circling consistently, unless you've got air data hooked up to it from an internal flight computer like a 302. Super common rookie move is to climb in ridge, convergence or wave where it can't get a sense of actual winds. Then trust the glide computer as you head off into a headwind "above glide."

Murphy's Law:
Glide computers work on theory. In theory your glider should get 40:1. In theory lift and sink will balance out. In theory the winds will be consistent. Trusting all of those theories to correlate and work out will eventually put you in a position where you will either land out, or at least need to change plans, stop and thermal, do something.

No Final Glide Mode:
Some flight computers don't take winds into consideration in final glide when you are looking to cover max distance over the ground. This means that flying into a headwind, the speed director may not tell you to fly faster than best glide.


Mountains in the way:

Older pure GPS, no map/terrain systems don't know about that mountain in front of you. If things behind the mountain are disappearing, you're not getting over it and better have an option.

*** The Good:

Wind Calculations:
XCSoar with it's GPS based winds is usually within a few degrees and a knot or two of my L-Nav that has airspeed data as well. Close enough for government work if I'm circling and winds are generally consistent.

Wind Input: XCSoar will let me manually update the wind so that I can tell it that I know I'm circling in3 knots , but I'm about to leave the convergence and fly into a 10 knot headwind for 30 miles.

Safety Margins:
Arrival Heights of 1000agl can help with Murphy's Law.

Either using a high MC value like 4.0 and then flying MC0 or using the Polar Degradation feature in XCSoar, you can further buffer against counting on published glide performance.


User Errors I've seen or done:

Wrong Polar: Jumping in the club 1-26 with your PDA still configured for an ASW-20. Makes for bold moves.

Wrong Arrival Height: Thinking your arrival height is 1000agl. Not realizing it is for 0AGL or 500AGL.


The main thing is to not blindly trust or depend on a flight computer. Have a notion of what seems correct and use that in your head to validate what the flight computer says.

On Thursday, May 30, 2013 9:14:58 PM UTC+2, wrote:
the iPAQ won't run later versions of XCSoar gracefully.

I havn't seen your ticket on the XCSoar bug tracker about this problem.

On Thursday, May 30, 2013 3:11:41 PM UTC-7, Max Kellermann wrote:
On Thursday, May 30, 2013 9:14:58 PM UTC+2, wrote: the iPAQ won't run later versions of XCSoar gracefully. I havn't seen your ticket on the XCSoar bug tracker about this problem.

Pobably because I never opened a ticket. I brought it up on the XCSoar forum, but the consensus was that the old 3850 just didn't have the processing power. The later versions of XCSoar run great on the Dell Streak, but mine has a problem with the pins on the connector, and the cable doesn't fully connect. No connection, no charge, short flights.

I agree with regular sense checking what any computer tells you. My first example is that I always check when I enter the task that the distance is what I expect (from planning it on the PC), and that the climb distance required for the whole task makes some sort of sense. Then I check the arrival height at the base airport so I know the arrival safety height is set as I expect, and my personal preference is to enter a bug setting - cause I prefer my final glide calculations to be slightly pessimistic. I sense check the wind by comparing ground speed to airspeed.

Long before final glide, I review how the remaining climb required is changing over time, to see whether I am very broadly under or over achieving. I also do a sense check of 100 foot per k, and see how actual performance compares with that.

Recently, in my own glider I have been using an LX 9000 - absolutely superb, no issues, among the biggest benefits are the absolute absence of lag either when turning in a thermal or when zooming the display, and the excellent wind calculation - and in other gliders I have been using a GliderGuider (same as Vertica V2 and Avier) running SeeYou Mobile and using only the internal GPS, with a Socket Mobile power pack bought from Paul Remde for power.. This has also been excellent with no issues. On a recent flight in our club Duo, I had the GliderGuider and my co-pilot had an Oudie 2, both running SYM with the same setup. Screen brightnesses were the same - entirely clear even with the brightest sunlight from every direction. The extra brightness of these devices makes a real difference by comparison with devices I have had before - iPaqs 3850/3950/4700, Oudie 1 - you can take in the info so much more quickly and you don't have to bother about whether the screen is pointed in just the right direction.

The Oudie occasionally gave random wind readings presumably because of the known 'track smoothing' issue affecting its internal GPS, but also predictably the Oudie gave slightly quicker screen redraw after some actions.

I have XC Soar on a Nexus 7 and IGlide Light on my iPhone. Neither has a bright enough screen by comparison with the GG/Oudie 2 etc.

This is all slightly away from the question of errors made - for which I would offer a couple of examples of my own error in earlier years. Once I started a comp with the previous year's turnpoint file in my devices - very stupid, sure enough a new turnpoint was set on the first day, I did not have time to enter it, thought I could do it by eye and got a penalty for turning just outside the sector. And on another occasion, having taken off without adequate flight planning, I got an airspace warning while in a strong climb, cancelled it thinking that it was for something which did not affect me, and then a minute later realised that it did affect me - when I had already climbed into forbidden airspace. Both examples of **** Poor Preparation.

Hope someone finds this interesting.

Mark Burton, London Gliding Club, UK

On Thursday, 30 May 2013 17:03:40 UTC+1, son_of_flubber wrote:
It would be useful to hear your tales of soaring software crashing and/or providing misleading or inaccurate information. Please be specific.



It would also be good to hear about cases of "user error" where you made a mistake in either setting up the device, misinterpreting the information displayed, or you found yourself confused or mislead by the way the information was presented. Of particular interest would be pitfalls that you stumbled upon in flight and how you resolved the difficulty.



I'd also like to hear about any cases of two devices running in parallel and presenting conflicting or diverging information (for example different indications of wind direction/speed or final glide arrival height).

On Thursday, 30 May 2013 17:03:40 UTC+1, son_of_flubber wrote:
It would be useful to hear your tales of soaring software crashing and/or providing misleading or inaccurate information. Please be specific.



It would also be good to hear about cases of "user error" where you made a mistake in either setting up the device, misinterpreting the information displayed, or you found yourself confused or mislead by the way the information was presented. Of particular interest would be pitfalls that you stumbled upon in flight and how you resolved the difficulty.



I'd also like to hear about any cases of two devices running in parallel and presenting conflicting or diverging information (for example different indications of wind direction/speed or final glide arrival height).

PS When running more than one device, if the final glide calculations are different I tend to believe whichever is more pessimistic! But actually it is normally because of different wind figures, and you can decide which is more credible.

On Thursday, May 30, 2013 12:03:40 PM UTC-4, son_of_flubber wrote:
It would be useful to hear your tales of soaring software crashing and/or providing misleading or inaccurate information. Please be specific.



It would also be good to hear about cases of "user error" where you made a mistake in either setting up the device, misinterpreting the information displayed, or you found yourself confused or mislead by the way the information was presented. Of particular interest would be pitfalls that you stumbled upon in flight and how you resolved the difficulty.



I'd also like to hear about any cases of two devices running in parallel and presenting conflicting or diverging information (for example different indications of wind direction/speed or final glide arrival height).

At the Bus Class medium performance 2 place race at Wurtsboro last year, I was flying with a newcomer to racing. He's a CFI/CFIG, FO for a major airline, and aerospace engineering type. I'm a 25 year racing pilot, CFIG, with lots of XC and flight display experience.

Between the two of us, we couldn't figure out what the new (to us) open source flight display was telling us as we got down to rounding a final AAT turnpoint and trying to get home. Was it telling us glide to the turnpoint? Around the turnpoint to finish? Glide home from current position? Finally after removing shoes and socks and dividing by pi, I was able to figure out that we were fat with altitude to get home, but not before we had a couple of minutes of circling in a half knot while we tried to make sense of what we were seeing.

Just another one of those cases where familiarity with the increasingly sophisticated displays is best gained before it's crunch time.

P3

Keep it coming guys. I'd expect that this stuff is also very helpful to the quiet newbies that lurk in this group.

On Friday, May 31, 2013 12:57:36 AM UTC+2, Uncle Fuzzy wrote:
I brought it up on the XCSoar forum, but the consensus was that the old 3850 just didn't have the processing power.

Which is bull****.