Implausible Time Records

Looks like both you and Dan show a UBLOX NEO as the GPS receiver, maybe
a problem with new firmware from the vendor?



On 5/19/19 7:03 AM, wrote:
Dan,
Just FYI, I got the same error last night on an IGC flle from an Lx9070, so it may not be a CN issue.
lx9070 was updated to latest software version on 4/8/19.

This is what I see in my file:
B1813373310143N08621921WA0103001106006001113851177 3067-006602030130-041003
B1813383310151N08621903WA0103001106007004113561204 1053-004602030130-043003
B1813393310164N08621887WA0103001107006004111961228 5040-003602030130-042003
LLXVCLOCKJUMP
B1813373310179N08621875WA0103101107006004110891250 7026-003602030120-039003
B1813383310197N08621867WA0103201107006004110021274 0014-004102030120-038001
B1813393310216N08621863WA0103101107006004109261299 2002-004102030120-034001

Kinsell, You may be on the right track.
Backup recorder (portable powerflarm) with separate gps system, recorded fine during the same period.

On 5/20/19 6:43 AM, wrote:
Kinsell, You may be on the right track.
Backup recorder (portable powerflarm) with separate gps system, recorded fine during the same period.


I notice your Oct 2 2018 flight on OLC had that peculiar highly
compressed altitude graph, but without the gps altitude dropouts. Maybe
that's just some unrelated OLC display issue.

Ublox receivers are used for many other applications besides flight
recorders, wonder why nobody else seems to be having problems.

I've been submitting from a PF Core the last few years, haven't seen any
of these issues.

Ref .
I notice your Oct 2 2018 flight on OLC had that peculiar highly
compressed altitude graph, but without the gps altitude dropouts. Maybe
that's just some unrelated OLC display issue.

Good observation, I didn’t notice that.
The one on 10/4 has the same compressed altitude issue, while the one on 10/3 looks ok, as does the flight on 5/1/19.
I have been posting to OLC from that particular 9070 for about 4 years and haven’t had a problem before now.

MS

On 5/20/19 9:45 AM, wrote:
Ref .
I notice your Oct 2 2018 flight on OLC had that peculiar highly
compressed altitude graph, but without the gps altitude dropouts. Maybe
that's just some unrelated OLC display issue.

Good observation, I didn’t notice that.
The one on 10/4 has the same compressed altitude issue, while the one on 10/3 looks ok, as does the flight on 5/1/19.
I have been posting to OLC from that particular 9070 for about 4 years and haven’t had a problem before now.

MS


Also I notice your Oct 2 log had a 2 second backwards jump in the time
stamp, nicely pointed out by a CLOCKJUMP message.


B1836063309906N08617890WA0079300914008999092601063 91370014102310100
B1836073309895N08617877WA0079700918008999099341052 61320019502310100
B1836083309885N08617862WA0080100922008999096891031 41260027202310100
B1836093309877N08617847WA0080400926008999097381021 11210032602300100
LLXVCLOCKJUMP
B1836073309869N08617831WA0080900931008999091120999 41150032402300110
B1836083309863N08617815WA0081500936008999087500984 01100029902300090
B1836093309859N08617798WA0081800940008999092360980 91040030802290090
B1836103309856N08617781WA0082200942008999096080987 51000036802290080



So these problems have been around for quite a while, maybe OLC just
started flagging them as fatal errors?

On 5/20/19 1:05 PM, kinsell wrote:
On 5/20/19 9:45 AM, wrote:
Ref .
I notice your Oct 2 2018 flight on OLC had that peculiar highly
compressed altitude graph, but without the gps altitude dropouts.Â* Maybe
that's just some unrelated OLC display issue.

Good observation, I didn’t notice that.
The one on 10/4 has the same compressed altitude issue, while the one
on 10/3 looks ok, as does the flight on 5/1/19.
I have been posting to OLC from that particular 9070 for about 4 years
and haven’t had a problem before now.

MS


Also I notice your Oct 2 log had a 2 second backwards jump in the time
stamp, nicely pointed out by a CLOCKJUMP message.


B1836063309906N08617890WA0079300914008999092601063 91370014102310100
B1836073309895N08617877WA0079700918008999099341052 61320019502310100
B1836083309885N08617862WA0080100922008999096891031 41260027202310100
B1836093309877N08617847WA0080400926008999097381021 11210032602300100
LLXVCLOCKJUMP
B1836073309869N08617831WA0080900931008999091120999 41150032402300110
B1836083309863N08617815WA0081500936008999087500984 01100029902300090
B1836093309859N08617798WA0081800940008999092360980 91040030802290090
B1836103309856N08617781WA0082200942008999096080987 51000036802290080



So these problems have been around for quite a while, maybe OLC just
started flagging them as fatal errors?


Looking at your Aug 2 2017 flight, it shows the same compressed altitude
graph, and another 2 second backwards jump in a time stamp. Wow.

Maybe he is exceeding VNE by a lot and going back in time? I wonder what Doc Brown would say.....LOL...

I’ve not heard back from Lxnav yet, but I had a private email from a very smart person that pointed out that both the October 2 and October 4 flights had the clock jump after takeoff but before soaring began. The flight this week had the clock jump a minute or so after soaring began, and thus is likely why OLC flagged this one and not the other two. It appears that the clock jump is 7 to 8 minutes after the unit is turned on. Since I generally do not turn the system on until just before takeoff, it is believed that the system is using an internal clock until it syncs with the gps satellites and then resets the clock which may be different by a couple of seconds. My plan is to turn the 9070 on a few minutes before launch to allow it to sync clocks to see if that helps. It is not clear to me if Dan’s issue is similar to mine or different.

MS