Weather reports coming in suggest rain for most of tomorrow and possibly high winds at ground level at our launch and recovery sites. In view of this information we are now 'No go' for launch this weekend.
As I suggested in an earlier post, our launch window is likely now closed until the new year, however the additional time may allow the construction of more receivers - as the saying goes: every cloud....
Friday, 30 October 2009
Weather update from Metcheck
All eyes are on the weekend weather as there is the potential for some really quite nasty weather to sweep in off the Atlantic on Sunday as a deepening low moves across the country.
Confidence is still rather low over the exact track this system will take, which in turn will affect where the heaviest rain and strongest winds occur. As things stand at the moment, the low looks set to deepen quickly as it approaches Britain and Ireland, with a possible north-eastwards track across southern Ireland and then across northern England. This would bring the heaviest rainfall across central parts of Britain, with the strongest winds to the south and east of the low.
Confidence is still rather low over the exact track this system will take, which in turn will affect where the heaviest rain and strongest winds occur. As things stand at the moment, the low looks set to deepen quickly as it approaches Britain and Ireland, with a possible north-eastwards track across southern Ireland and then across northern England. This would bring the heaviest rainfall across central parts of Britain, with the strongest winds to the south and east of the low.
Thursday, 29 October 2009
T minus 2 days
Another rollercoaster of a day with the weather models 00Z and 06Z models (both NOGAPS and GFS) suggesting that the nasty upper level winds out in the Atlantic would be coming over the UK just as we launch. Up at 9000 metres the indication was that wind speeds would be exceeding 100 knots! Our track was predicted to be almost 90 miles East of our launch site and to make matters worse heavy rain was also forecast.
I've just re-run the flight prediction based on the 12Z model and we have have a much more reasonable track. The rain is an unknown factor with no agreement in the models and different weather sites predicting wildly different weather. From what I can tell, cloud cover and the likely hood of rain falls as we move East - so we may be launching in cloudy skies and retrieving in clear ones.
Tomorrow is a VERY big D-day for us - fairly early on were going to have to give a 'go/no go' because we don't want to have delivery of Helium if it can't be used. So I'll be running the weather models tomorrow morning and hoping we have a consensus from the 00Z and 06Z runs.
This D-day is even bigger than that though. Our launch window is now closing due to factors such as team availability, daylight hours and weather considerations to name but a few. As such a launch between November and January is not particularly likely - so this may well be our last chance to launch in 2009.
As of this moment we are still 'GO'. Check back tomorrow to find out what D-day brings!
I've just re-run the flight prediction based on the 12Z model and we have have a much more reasonable track. The rain is an unknown factor with no agreement in the models and different weather sites predicting wildly different weather. From what I can tell, cloud cover and the likely hood of rain falls as we move East - so we may be launching in cloudy skies and retrieving in clear ones.
Tomorrow is a VERY big D-day for us - fairly early on were going to have to give a 'go/no go' because we don't want to have delivery of Helium if it can't be used. So I'll be running the weather models tomorrow morning and hoping we have a consensus from the 00Z and 06Z runs.
This D-day is even bigger than that though. Our launch window is now closing due to factors such as team availability, daylight hours and weather considerations to name but a few. As such a launch between November and January is not particularly likely - so this may well be our last chance to launch in 2009.
As of this moment we are still 'GO'. Check back tomorrow to find out what D-day brings!
Wednesday, 28 October 2009
T minus 3 days
GFS has been giving us wildly different predictions all day with 00Z, 06Z and 12Z model runs producing very different tracks. We still don't know if there will be rain, although the wind is likely to take our balloon North Westerly.
Currently still 'GO' for launch.
Currently still 'GO' for launch.
Tuesday, 27 October 2009
Avionics: Ready for flight
Here you can see, for the first time, the full avionics package loaded into the capsule. The long copper wire along the bottom is the transmit antenna and the small block on top is the GPS antenna.
GFS & NOGAPS: Massive disagreement
As I mentioned in an earlier post NOGAPS and GFS do not always agree... actually a lot of time they don't agree. However, sometimes the differences in them are really quite massive.
The charts below are for the same day and time and are off of the same model run. The coloured areas show the amount of precipitation that is expected to have fallen in the 12 hour period prior to the listed time - so in this instance between 0600-1800 on Saturday 31 October. As you can see they don't look very much alike. My gut instinct says NOGAPS is closer to being right and I really hope that's the case!
The charts below are for the same day and time and are off of the same model run. The coloured areas show the amount of precipitation that is expected to have fallen in the 12 hour period prior to the listed time - so in this instance between 0600-1800 on Saturday 31 October. As you can see they don't look very much alike. My gut instinct says NOGAPS is closer to being right and I really hope that's the case!
Camera and phone tests complete
The mobile phone is working perfectly having over 50% battery life even after well over 2 hours of tracking. The £5 credit loaded is going to be more than enough for our purposes.
Our camera ran for 1 hour and 23 minutes before running out of space on the card - but still with 25% battery remaining. I'm going to adjust the script to take 5 pictures a minute instead of 6 as we'd like to get a runtime of more than 100 minutes.
Our camera ran for 1 hour and 23 minutes before running out of space on the card - but still with 25% battery remaining. I'm going to adjust the script to take 5 pictures a minute instead of 6 as we'd like to get a runtime of more than 100 minutes.
T minus 4 days
A "Pay As You Talk" Vodafone SIM has now been acquired for our Windows Mobile device and is now having a full retest. At the same time the camera is also being retested with a 4Gb SDHC card (actually its an 8Gb card formatted to 4Gb!). The reason for dropping to 4Gb from 8 is that our CHDK firmware will not boot on the camera from a FAT32 partition.
Prediction on upper level winds have changed a little, showing an increase of 20 knots. We'll be monitoring the situation, but we are currently still 'go for launch'.
Prediction on upper level winds have changed a little, showing an increase of 20 knots. We'll be monitoring the situation, but we are currently still 'go for launch'.
Monday, 26 October 2009
Zephyrus 1 Launch: T minus 5 days
We've been looking at the predicted tracks and examining wind and rain predictions for this coming weekend and we're fairly happy with what we are seeing. No rain is predicted during daylight hours (top chart), upper winds are showing as being no higher than 60 knots (middle chart) and surface winds, although not ideal should still be below 15 knots (bottom chart). Upper and surface winds are showing as being SW on the NOGAPS model and WSW on the GFS model - and either would suit us.
We're now looking at a Saturday launch. Stay tuned.
Monday, 19 October 2009
Thursday, 15 October 2009
Weather decides whether (to launch)
With all the equipment pretty much ready to go, we are now at the mercy of the weather. Whilst rain is an issue - the wind is even more so. Our gas has to be ordered at least 24 hours before launch as the canister has to be hired by the week - which means we need to predict when we will have the right conditions. Just to make things that little bit more tricky, standard weather reports are of no use to us as surface winds give no indication of upper wind strength, or even direction!
We have access to a balloon flight prediction website (provided by Cambridge University) which gives forecasts for up to 120 hours ahead - but we cannot place complete faith in just this. Although many weather prediction models exist, none are accurate all of the time and often they models can disagree quite substantially.
Only a couple of models are available free to the public (most are expensive subscriptions): GFS, used by the aforementioned prediction website, and NOGAPS. The idea will be to combine the information from both models (which can be analysed for free on the US Navy's weather website) and using the website provided by CU.
At the moment the weekend doesn't look too promising, but I'll be checking later on as the models are re-run every six hours and drastic changes are not uncommon.
We have access to a balloon flight prediction website (provided by Cambridge University) which gives forecasts for up to 120 hours ahead - but we cannot place complete faith in just this. Although many weather prediction models exist, none are accurate all of the time and often they models can disagree quite substantially.
Only a couple of models are available free to the public (most are expensive subscriptions): GFS, used by the aforementioned prediction website, and NOGAPS. The idea will be to combine the information from both models (which can be analysed for free on the US Navy's weather website) and using the website provided by CU.
At the moment the weekend doesn't look too promising, but I'll be checking later on as the models are re-run every six hours and drastic changes are not uncommon.
Tuesday, 13 October 2009
Camera test complete
We currently only have a 2Gb card installed in our camera, which we now know needs to be replaced with an 8Gb for launch. Our test shows that we will use around 2Gb every 50 minutes - so we could theoretically get 200 minutes of footage with the higher capacity card. In reality though the batteries would not last for 200 minutes (and we expect our payload to have returned to Earth within 100 minutes).
Although not a 100% realistic test, for one I had to delete the contents of the memory card and restart the script, the battery lasted two full cycles. The CHDK/SDM software suggested there was still around 20-25% battery life left at the end of this test - a good indicator that we will have power for the entire duration of our flight.
Although not a 100% realistic test, for one I had to delete the contents of the memory card and restart the script, the battery lasted two full cycles. The CHDK/SDM software suggested there was still around 20-25% battery life left at the end of this test - a good indicator that we will have power for the entire duration of our flight.
No launch yet... Camera now undergoing testing
Weather over the weekend would have made a launch impossible... but thats not why we couldn't launch. The script being run by the camera kept activating the flash unit, which would have drained the batteries very quickly and would have been completely pointless.
Yesterday I finally perfected the script which also turns off the LCD backlight. The camera will take 8 pictures, 5 seconds apart, and then follow up with 20 seconds of video. After that the script will return to taking pictures.
As I write this the camera is now running this script to test how long the batteries will last. We would ideally like it to be able to run for 2 hours on a charge - but around 90 minutes will suffice.
Yesterday I finally perfected the script which also turns off the LCD backlight. The camera will take 8 pictures, 5 seconds apart, and then follow up with 20 seconds of video. After that the script will return to taking pictures.
As I write this the camera is now running this script to test how long the batteries will last. We would ideally like it to be able to run for 2 hours on a charge - but around 90 minutes will suffice.
Thursday, 8 October 2009
End to end test #1
A full end to end test has now been completed - including testing Andy's software which will keep us fully up-to-date on the balloon's exact position. This is the first time that the entire GPS/radio component of the avionics has been given a full shakedown. We have tested individual components - even to the point of seeing the GPS data in Hyperterminal, but this was the very first time that we had seen a live updated position in Google Earth (and Google Maps on Windows Mobile). I'm very happy to report that this first test was successful.
I do have my doubts as to whether we will be ready for launch this weekend. The camera still needs to be programmed to our specification and has to be fully tested. Phil is still concerned about our descent rate with our current 'chute and this also will need testing in conjunction with our 'release candidate' capsule. With so much achieved so far, well beyond our original concept (check the early posts!), we won't be rushing to launch before everything is confirmed to be flight ready.
Radio TX/RX - Flight Ready
Ground Antenna - Flight Ready
GPS Hardware - Flight Ready
Tracking Software - Flight Ready
Windows Mobile - Flight Ready
Camera - To be programmed
Gas (He) - To be purchased 24 hours before launch
Parachute - Testing required
Capsule - Testing required
Monday, 5 October 2009
End to end link now ready
The radio link is now eseentially complete and pretty much ready for flight. Andy is putting the finishing touches to the PCB, which is no more complicated than drilling a hole for the BNC connector. The link has been tested with the GPS unit and is working as expected - although we did need to make some additional configuration changes so that the 3D fix sentences were returned.
Hopefully we will have some video proof posted tomorrow :-)
Hopefully we will have some video proof posted tomorrow :-)
Thursday, 1 October 2009
Transmitter PCB made but launch delayed
Recently its been looking more and more likely that we would have to push our launch date back. We are moving along quite swiftly now, the transmitter's PCB has been given its acid bath and clean and is now ready for soldering. Despite this, we are going to have to delay by at least one week.
We're hoping to have the fully working transmitter by the end of play tomorrow, allowing for a full range of tests to be conducted over the weekend. The race will then be on to finish the camera scripts and to create the outer capsule.
As always, stay tuned!
We're hoping to have the fully working transmitter by the end of play tomorrow, allowing for a full range of tests to be conducted over the weekend. The race will then be on to finish the camera scripts and to create the outer capsule.
As always, stay tuned!
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