LOST P4P on Litchi Waypoint mission - Trying to locate downed bird. . .

[GFields]

Thanks for all the input/analysis, fellas. I walked the first three waypoints yesterday, paying especially close attention to the trees around points one and two, but unfortunately no joy.

I was flying a new version of a flight I've done many times, but I rushed when creating the mission and didn't take enough care in calculating elevations (specifically for the first two WPs). All of the biggest lessons I've learned flying have come from crashes, unfortunately. So I'll put "hastily creating and launching Litchi waypoint mission" in my 'don't do this' column. I'm heading to town to replace the drone before the wife notices its gone (for NOT the first time). . .

Thanks again for your assistance. I haven't given up on finding the bird, but at this point I'm not very confident in achieving any result. Perhaps some recon from the air will do the trick for me. And hopefully this will be the last time I enlist your expertise for such a dilemma.

Cheers,

When using Litchi Waypoint Missions it is very important to give instructions for when the mission ends RTH ect. If you select hover, it will do that and then go down once the battery has completely discharged. I have learned that you can trust Litchi Waypoint Mission to complete if/when signal is lost. However, it is very important that you take the time to review eaxh waypoint checking for altitude and speed. With those being correct, you can relax the mission will be carried out as instructed. I have crashed two different drones using the Litchi Waypoint mission and both were the result of my setting the altitude too low at one point. Good luck in finding your drone.

 

[offroadpyro]

Ah litchi waypoints.Yes you can't lose signal but it will use GPS and continue until completing mission.You switched it off after loss of signal so I think it stayed on mission.It has to be between last waypoint and next one.Also you may not be able to find it.It could be in the top of the tree.I had to get mine pulled out of 175 foot try by a tree climber.So if you plan on another drone and use litchi.After you plan mission click on wrench.Then bottom choice, dotted lines.Choose select all and edit.You then can change where you select altitude you ( follow ground)..If you don't and you are at 200 feet and you come to a mountain.Crash.!!..litchi automatic sets it to relative to home for altitude.You can change it to relative to ground.It goes by Google map so 15 meters extra helps.I know it's to late now but if you try again learn about that option.If your going to fly waypoints you absolutely need to change that.Sorry about your bird..

 

[Marko5584]

Sorry if this is a bit late...

If you have not found it, you might walk the path of your waypoint mission with your device (phone or tablet) in hand so you can see your position on the app during the walk. I lost a P3 last year on a Litchi run and found it a few days later under a cluster of trees which were at the highest point of the waypoint run. Pilot error. I did not know trees were so high there. ten feet higher I would have cleared it.

http://www.planetcanadice.com/Movies/CrashInTrees.mp4

I walked my waypoint run backwards with my phone in hand and the Litchi route visible on my phone and found it.

I have lost signal numerous times in Litchi , but the bird returns. Google earth is useful for plotting waypoint routes.

 

[Fly Dawg]

Google earth is useful for plotting waypoint routes.

Use extreme caution using that. It is relatively accurate, but always add extra. GE's terrain is only so accurate, so grain of salt there. Just saying.

 

[sar104]

Rookie litchi dumb dumb lost my drone shortly after launching yesterday.

I was in my driveway when I launched Litchi waypoint mission (where I fly all the time) and was taken by surprise when I lost signal moments after it started its mission. The first thing I tried was to pause the mission by pushing pause on my screen), then I switched to ATTI and then GPS mode while full throttling up, to avoid the trees. I figured the drone would be hovering in place when I got there, but it wasn't so I quickly drove the path of my mission watching my controller status light, but it never came back on. I waited at the last waypoint of the mission before returning home then to the last known location of the bird. I searched the ground but couldn't see anything, and had a hard time seeing into the trees; there are a lot of em and they're very snowy.

My theory was that the drone must have crashed soon after i lost contact with RC, otherwise I would have regained connection while mimicking the waypoint route, or while waiting at the end of the route. The only thing that makes sense is that I lost all contact because the bird crashed and lost power when the battery came out...

Trying to decipher log info, looks to me like drone crashed into tall tree at its last known location? Any suggestions, opinions welcome. . .
Guess I'll return to the last know location and look some more. Feel like an idiot as I know Litchi waypoint missions can be risky without ample planning. Guess I'll take it as another expensive flying lesson.

Link to my flight log:
Airdata UAV - Flight Data Analysis for Drones

Cheers and thanks for any help.
Luke

There's not too much to add to the discussion above except to look more closely at the flight altitude profile AGL. Firstly, as noted, there is no evidence that you actually lost uplink or downlink when you initially paused and then switched to ATTI, even though the signal quality did fall a little. And the aircraft had resumed executing the Litchi mission when you did lose contact in the vicinity of the first waypoint due to loss of downlink:

Uplink was still reasonable, and so any further attempted mode changes after that point might have been accepted, but with downlink gone we don't see anything. So - it either continued on the mission or, if you switched it again to GPS or ATTI it may have hovered or drifted off.

If it did continue the mission, the next problem is clearly evident in the flight profile. Calculating the fully resolved flight altitude above ground level gives the following:

Looking at GE street view, the trees in the vicinity of WP2 are clearly taller than 24 m, which was the ground clearance at that waypoint. So, if it continued the mission, then it is most unlikely that it made it past WP2 without hitting something.

 

[Harleydude]

I would consider the possibility that your battery slipped out. I have been flying RC for years. So in the spirit of "finding all issues BEFORE I fly," I found a video regarding the "double click" of the Phantom battery. I can't find it now, but it's pretty easy to test, and the guy was right. You can push the battery in and get a single click, which leaves you with the illusion that it is installed properly. You have to wiggle the battery and give it an extra push for the bottom latch to click.

Dollars to doughnuts, if you ever do find the bird, the battery is probably dislodged.

 

[sar104]

I would consider the possibility that your battery slipped out. I have been flying RC for years. So in the spirit of "finding all issues BEFORE I fly," I found a video regarding the "double click" of the Phantom battery. I can't find it now, but it's pretty easy to test, and the guy was right. You can push the battery in and get a single click, which leaves you with the illusion that it is installed properly. You have to wiggle the battery and give it an extra push for the bottom latch to click.

Dollars to doughnuts, if you ever do find the bird, the battery is probably dislodged.

It certainly happens, but what makes you suspect that in this case? The log data clearly suggest that the disconnect was a result of gradual loss of signal, and the flight profile suggests that the mission could not be completed due to obstacles. I see no reason to invoke another unnecessary failure mode to explain the event.

 

[Harleydude]

It certainly happens, but what makes you suspect that in this case? The log data clearly suggest that the disconnect was a result of gradual loss of signal, and the flight profile suggests that the mission could not be completed due to obstacles. I see no reason to invoke another unnecessary failure mode to explain the event.

Losing signal doesn't down the bird. Something catastrophic happened at the end of the flight log. I doubt the drone lost signal from a mere 1500' away @ 208' AGL without some kind of catastrophic event. So I think it's safe to assume the drone went down at the last data point, as opposed to losing signal, continuing on its mission, and THEN possibly crashing AFTER the last data point. I think it's a safe bet that the drone crashed on or near the building shown in the airdata.com photo. The property owner may have picked it up.

Furthermore, I doubt there were any obstacles @ 208'. Even if one takes into account the elevation increase from launch site to last data point, the drone appears to increase altitude as the terrain increased in elevation. I can only assume the waypoint program did this.

Worth noting, the tallest trees in Alaska are no taller than 150' tops. The drone had already cleared a large section of forest at the last data point.

With all this information, it seems very plausible that the drone simply lost power from a dislodged battery and crashed on private property. While I can't be 100% sure, I think dismissing this possibility would be foolish.

D

 

[sar104]

Losing signal doesn't down the bird. Something catastrophic happened at the end of the flight log. I doubt the drone lost signal from a mere 1500' away @ 208' AGL without some kind of catastrophic event. So I think it's safe to assume the drone went down at the last data point, as opposed to losing signal, continuing on its mission, and THEN possibly crashing AFTER the last data point. I think it's a safe bet that the drone crashed on or near the building shown in the airdata.com photo. The property owner may have picked it up.

Furthermore, I doubt there were any obstacles @ 208'. Even if one takes into account the elevation increase from launch site to last data point, the drone appears to increase altitude as the terrain increased in elevation. I can only assume the waypoint program did this.

Worth noting, the tallest trees in Alaska are no taller than 150' tops. The drone had already cleared a large section of forest at the last data point.

With all this information, it seems very plausible that the drone simply lost power from a dislodged battery and crashed on private property. While I can't be 100% sure, I think dismissing this possibility would be foolish.

D

No - that's not correct. There is no catastrophic event recorded in the log, and the downlink signal strength clearly decreases to zero over the flight path from 300 and 550 m, not even close to instantaneously as would be expected from a catastrophic failure. The uplink signal strength also decreases steadily, but the record does not show it going to zero. Why the signal was so poor at relatively short distance is unclear, but the steady decrease in uplink and downlink almost completely rules out a catastrophic cause for the downlink loss, and there is no reason at all to suppose that the aircraft crashed at the point of downlink loss. There is also nothing to suggest that the aircraft did not continue on its Litchi mission after downlink loss. If it did continue then it most likely ran into obstacles around WP2, since its programmed ground clearance was only 24 m at that point.

In summary, your safe bets and firm conclusions all appear to me to be based on assumptions that are entirely unsupported by the data, so possible, but not indicated as likely at all.

 

[Wahoo_Ace]

Can the OP chime in to let us know the status? Have you found it?

 

[Harleydude]

No - that's not correct. There is no catastrophic event recorded in the log,

The log file wouldn't log a loss of power - because there's no power for the CPU to create a log.

and the downlink signal strength clearly decreases to zero over the flight path from 300 and 550 m, not even close to instantaneously as would be expected from a catastrophic failure.

While I concede that the drone may have lost signal (which is strange from only 1500' away), I still hold firm the assertion that the gradual loss of downlink signal does NOT mean the drone crashed. It's not uncommon to lose signal during waypoint missions, albeit, odd that it would lose signal @ only 1500'. But even then, the drone was clearly ascending to match the terrain. One must assume that the drone continued to maintain its clearance over the trees. While I concede that 158' isn't a lot of net altitude, it should've been enough to clear the trees in that area.

If you look at the waypoint mission, the drone was on a fairly aggressive ascent from WP2 (24 meters) to WP3 (to roughly 95 meters). This is consistent with the log files that show the drone ascending, right up to the point it lost connection @ 208' AGL. WP1 seems erroneous to me, and should probably be tossed aside. So....unless we have reason to believe that the drone leveled off (which would directly conflict with the log files) or hit a tower, we can only assume that it continued its ascent, thus clearing all natural objects (trees).

The uplink signal strength also decreases steadily, but the record does not show it going to zero. Why the signal was so poor at relatively short distance is unclear, but the steady decrease in uplink and downlink almost completely rules out a catastrophic cause for the downlink loss,

I disagree. I see no reason, other than catastrophic failure, why the uplink would end so abruptly. A power loss would explain why the log just ends while we still have uplink signal. Remember, "downlink" is the signal used to control the bird. "Uplink" is the telemetry data. So, in theory, as long as the bird still has an uplink connection, the iPad should have continued to generate a log. We never see a complete loss of uplink signal. We simply see the log file end abruptly. This screams "power failure" to me. If there were 15-story buildings around, I would've guessed that the drone crashed into a building. I lieu of buildings or other tall structures, power loss seems the most likely scenario.

and there is no reason at all to suppose that the aircraft crashed at the point of downlink loss.

Agreed. Downlink is for control. Uplink is video and telemetry data. A catastrophic event is the *only* reason why we'd see the log file end while we still had uplink signal. The abrupt end to the log file while still essentially connected makes me believe that the loss of signal was due to a catastrophic event.

There is also nothing to suggest that the aircraft did not continue on its Litchi mission after downlink loss.

Agreed. But worth noting, had the drone *not* crashed, we would see a *gradual* loss of uplink signal to mach the gradual loss of downlink signal. We didn't see that. Uplink signal ends abruptly, indicating a catastrophic event.

If it did continue then it most likely ran into obstacles around WP2, since its programmed ground clearance was only 24 m at that point.

This is what makes zero sense to me. We have an inconsistency in data. According to the log file, the vehicle ascended to 158' directly, and then moved on to the next waypoint, constantly ascending as it moved horizontally. But according to the waypoint *graph*, the vehicle STARTS @ 64 meters and DESCENDS to 24 meters. I don't know where that waypoint graph came from or what it's basing its altitude curve on, but it completely conflicts with the log file data. I would dismiss it.

In summary, your safe bets and firm conclusions all appear to me to be based on assumptions that are entirely unsupported by the data...

I disagree. A gradual loss of downlink signal is natural. An uplink signal loss would follow the same curve. Instead, we see an abrupt halt in the log file while we still have uplink signal. To me, that says "catastrophic event."

No - that's not correct. There is no catastrophic event recorded in the log,

The log file wouldn't log a loss of power - because there's no power for the CPU to create a log.

and the downlink signal strength clearly decreases to zero over the flight path from 300 and 550 m, not even close to instantaneously as would be expected from a catastrophic failure.

Agreed. I concede that the drone gradually lost downlink signal (which is strange from only 1500' away). But it's not uncommon to lose signal during waypoint missions, albeit, odd that it would lose signal @ 1500' out. But worth noting is that the drone clearly ascended to match the terrain. So one must conclude that the drone continued to maintain its clearance over the trees. While I concede that 158' isn't a lot of net altitude, it should've been enough to clear the trees in that area.

If you look at the waypoint mission, the drone was on a fairly aggressive ascent from WP2 (24 meters) to WP3 (to roughly 95 meters). This is consistent with the log files that show the drone ascending, right up to the point it lost connection @ 208' AGL. So....unless we have reason to believe that the drone leveled off or hit a tower, we can only assume that it continued its ascent, thus clearing all natural objects. WP1 makes zero sense to me. According to the log files, the drone never ascended from 64m to 24m.

The uplink signal strength also decreases steadily, but the record does not show it going to zero. Why the signal was so poor at relatively short distance is unclear, but the steady decrease in uplink and downlink almost completely rules out a catastrophic cause for the downlink loss,

I disagree. I see no reason, other than catastrophic failure, why the uplink would end so abruptly. A power loss would explain why the log just ends while we still have uplink signal. Remember, "downlink" is the signal used to control the bird. "Uplink" is the telemetry data. So, in theory, as long as the bird still has an uplink connection, the iPad should have continued to generate a log. We never see a complete loss of uplink signal. We simply see the log file end abruptly. This screams "power failure" to me. If there were 15-story buildings around, I would've guessed that the drone crashed into a building. I lieu of buildings or other tall structures, power loss seems the most likely scenario.

and there is no reason at all to suppose that the aircraft crashed at the point of downlink loss.

Agreed. That said, a catastrophic event is the *only* reason why we'd see the log file end while we still had uplink signal. The abrupt end to the log file while still essentially connected makes me believe that the loss of signal was due to a catastrophic event.

There is also nothing to suggest that the aircraft did not continue on its Litchi mission after downlink loss.

Agreed. But, had the drone *not* crashed, we would see a *gradual* loss of uplink signal to mach the gradual loss of downlink signal. We didn't see that. Uplink signal ends abruptly, indicating a catastrophic event.

If it did continue then it most likely ran into obstacles around WP2, since its programmed ground clearance was only 24 m at that point.

This is what makes zero sense to me. We have an inconsistency in data. According to the log file, the vehicle ascended to 158' directly, and then moved on to the next waypoint, constantly ascending as it moved horizontally. But according to the waypoint *graph*, the vehicle STARTS @ 64 meters and DESCENDS to 24 meters. I don't know where that waypoint graph came from or what it's basing its altitude curve on, but it completely conflicts with the log file data. I would dismiss it.

In summary, your safe bets and firm conclusions all appear to me to be based on assumptions that are entirely unsupported by the data...

I disagree. A gradual loss of downlink signal is natural. An uplink signal loss would follow the same curve. Instead, we see an abrupt halt in the log file while we still have uplink signal. This says "catastrophic event" to me.

, so possible, but not indicated as likely at all.

I disagree. Based on the available data, I think a loss of power is very likely. But you have to dismiss the waypoint altitude graph, which doesn't jibe at all with the log files.

Thoughts?

 

[sar104]

The log file wouldn't log a loss of power - because there's no power for the CPU to create a log.




While I concede that the drone may have lost signal (which is strange from only 1500' away), I still hold firm the assertion that the gradual loss of downlink signal does NOT mean the drone crashed. It's not uncommon to lose signal during waypoint missions, albeit, odd that it would lose signal @ only 1500'. But even then, the drone was clearly ascending to match the terrain. One must assume that the drone continued to maintain its clearance over the trees. While I concede that 158' isn't a lot of net altitude, it should've been enough to clear the trees in that area.

If you look at the waypoint mission, the drone was on a fairly aggressive ascent from WP2 (24 meters) to WP3 (to roughly 95 meters). This is consistent with the log files that show the drone ascending, right up to the point it lost connection @ 208' AGL. WP1 seems erroneous to me, and should probably be tossed aside. So....unless we have reason to believe that the drone leveled off (which would directly conflict with the log files) or hit a tower, we can only assume that it continued its ascent, thus clearing all natural objects (trees).




I disagree. I see no reason, other than catastrophic failure, why the uplink would end so abruptly. A power loss would explain why the log just ends while we still have uplink signal. Remember, "downlink" is the signal used to control the bird. "Uplink" is the telemetry data. So, in theory, as long as the bird still has an uplink connection, the iPad should have continued to generate a log. We never see a complete loss of uplink signal. We simply see the log file end abruptly. This screams "power failure" to me. If there were 15-story buildings around, I would've guessed that the drone crashed into a building. I lieu of buildings or other tall structures, power loss seems the most likely scenario.





Agreed. Downlink is for control. Uplink is video and telemetry data. A catastrophic event is the *only* reason why we'd see the log file end while we still had uplink signal. The abrupt end to the log file while still essentially connected makes me believe that the loss of signal was due to a catastrophic event.





Agreed. But worth noting, had the drone *not* crashed, we would see a *gradual* loss of uplink signal to mach the gradual loss of downlink signal. We didn't see that. Uplink signal ends abruptly, indicating a catastrophic event.





This is what makes zero sense to me. We have an inconsistency in data. According to the log file, the vehicle ascended to 158' directly, and then moved on to the next waypoint, constantly ascending as it moved horizontally. But according to the waypoint *graph*, the vehicle STARTS @ 64 meters and DESCENDS to 24 meters. I don't know where that waypoint graph came from or what it's basing its altitude curve on, but it completely conflicts with the log file data. I would dismiss it.





I disagree. A gradual loss of downlink signal is natural. An uplink signal loss would follow the same curve. Instead, we see an abrupt halt in the log file while we still have uplink signal. To me, that says "catastrophic event."






The log file wouldn't log a loss of power - because there's no power for the CPU to create a log.




Agreed. I concede that the drone gradually lost downlink signal (which is strange from only 1500' away). But it's not uncommon to lose signal during waypoint missions, albeit, odd that it would lose signal @ 1500' out. But worth noting is that the drone clearly ascended to match the terrain. So one must conclude that the drone continued to maintain its clearance over the trees. While I concede that 158' isn't a lot of net altitude, it should've been enough to clear the trees in that area.

If you look at the waypoint mission, the drone was on a fairly aggressive ascent from WP2 (24 meters) to WP3 (to roughly 95 meters). This is consistent with the log files that show the drone ascending, right up to the point it lost connection @ 208' AGL. So....unless we have reason to believe that the drone leveled off or hit a tower, we can only assume that it continued its ascent, thus clearing all natural objects. WP1 makes zero sense to me. According to the log files, the drone never ascended from 64m to 24m.




I disagree. I see no reason, other than catastrophic failure, why the uplink would end so abruptly. A power loss would explain why the log just ends while we still have uplink signal. Remember, "downlink" is the signal used to control the bird. "Uplink" is the telemetry data. So, in theory, as long as the bird still has an uplink connection, the iPad should have continued to generate a log. We never see a complete loss of uplink signal. We simply see the log file end abruptly. This screams "power failure" to me. If there were 15-story buildings around, I would've guessed that the drone crashed into a building. I lieu of buildings or other tall structures, power loss seems the most likely scenario.





Agreed. That said, a catastrophic event is the *only* reason why we'd see the log file end while we still had uplink signal. The abrupt end to the log file while still essentially connected makes me believe that the loss of signal was due to a catastrophic event.





Agreed. But, had the drone *not* crashed, we would see a *gradual* loss of uplink signal to mach the gradual loss of downlink signal. We didn't see that. Uplink signal ends abruptly, indicating a catastrophic event.





This is what makes zero sense to me. We have an inconsistency in data. According to the log file, the vehicle ascended to 158' directly, and then moved on to the next waypoint, constantly ascending as it moved horizontally. But according to the waypoint *graph*, the vehicle STARTS @ 64 meters and DESCENDS to 24 meters. I don't know where that waypoint graph came from or what it's basing its altitude curve on, but it completely conflicts with the log file data. I would dismiss it.





I disagree. A gradual loss of downlink signal is natural. An uplink signal loss would follow the same curve. Instead, we see an abrupt halt in the log file while we still have uplink signal. This says "catastrophic event" to me.



I disagree. Based on the available data, I think a loss of power is very likely. But you have to dismiss the waypoint altitude graph, which doesn't jibe at all with the log files.

Thoughts?

First observation - you have uplink and downlink confused. Uplink is control. Downlink is telemetry and video. Downlink went to zero in the log over several hundred meters, not discontinuously. That's not a catastrophic event.

Second observation - the log stops around WP1. There are no data after that. WP2 was only 24 m AGL - the lowest AGL on the mission. A quick look at GE Street View is enough to show that the trees there are taller than that.

If you consider those two points then I suspect that you will come to the same conclusion that I did.

 

[Harleydude]

First observation - you have uplink and downlink confused. Uplink is control. Downlink is telemetry and video.

Are you sure about that? My understanding that the log speaks from the drone's perspective, not the iPad's. Now...granted...I'm not 100% sure on this, but I'm fairly certain. I wouldn't even know where to research this. The DJI site is a dearth of information and the support lemmings are clueless. If you say you're sure about this, I'll go along with it. It would appreciate it if you had some supporting documents.

Downlink went to zero in the log over several hundred meters, not discontinuously. That's not a catastrophic event.

Well, if your "uplink/downlink" correct is true, then this means the bird could have kept flying long after losing downlink signal...which concurs with your statement.

Second observation - the log stops around WP1. There are no data after that. WP2 was only 24 m AGL - the lowest AGL on the mission. A quick look at GE Street View is enough to show that the trees there are taller than that.

WP1 starts @ 64 meters. Can you explain that? And then, despite the terrain the East increasing in elevation, sends the bird to 24 meters @ WP2. Nothing about that makes any sense. With all due respect to the OP, one would have to be seriously challenged to send a drone UP a hill in a forested area with a program that tells it to descend immediately.

If you consider those two points then I suspect that you will come to the same conclusion that I did.

Touché. I do. But now I just have more questions:

1) As long as I've been flying waypoints, WP1 is always 0 feet AGL. Granted; I've never used Litchi. But I assume it runs on the same basic premise as any other WP software. So how does the Waypoint graph START @ 64 feet?

2) I don't know any WP software that allows you to program descending waypoints. Again, maybe Litchi is different. And I could see how that could be a useful feature. But certainly it would issue some sort of warning to the user that WP2 is LOWER than WP1????

Things that make ya go, "Hmmmmmm....."

 

[sar104]

Are you sure about that? My understanding that the log speaks from the drone's perspective, not the iPad's. Now...granted...I'm not 100% sure on this, but I'm fairly certain. I wouldn't even know where to research this. The DJI site is a dearth of information and the support lemmings are clueless. If you say you're sure about this, I'll go along with it. It would appreciate it if you had some supporting documents.

I've seen no documentation on that but that convention for naming is consistent with standard telemetry convention. Additionally, having analyzed tens of logs, I can say out that connection is always reported lost when the downlink, not the uplink, goes to zero.

Well, if your "uplink/downlink" correct is true, then this means the bird could have kept flying long after losing downlink signal...which concurs with your statement.





WP1 starts @ 64 meters. Can you explain that? And then, despite the terrain the East increasing in elevation, sends the bird to 24 meters @ WP2. Nothing about that makes any sense. With all due respect to the OP, one would have to be seriously challenged to send a drone UP a hill in a forested area with a program that tells it to descend immediately.

Waypoints elevation is whatever you set it to. There is no mystery here - you can view this Litchi mission yourself in mission hub. WP1 is 63.8 m. WP2 is 59 m. I cannot comment on why the OP set that lower, but it is.

Touché. I do. But now I just have more questions:

1) As long as I've been flying waypoints, WP1 is always 0 feet AGL. Granted; I've never used Litchi. But I assume it runs on the same basic premise as any other WP software. So how does the Waypoint graph START @ 64 feet?

2) I don't know any WP software that allows you to program descending waypoints. Again, maybe Litchi is different. And I could see how that could be a useful feature. But certainly it would issue some sort of warning to the user that WP2 is LOWER than WP1????

Things that make ya go, "Hmmmmmm....."

Sorry - I guess Litchi is different to whatever you are familiar with.