HedgeTrimmer Posted at 2018-10-27 15:03
As the moving air is pushed over a mountain range it is squeezed between the mountains and the top of the troposphere, causing the wind to speed up.

Please provide Link(s) to where it states wind speed increases due to air being squeezed between mountains and "top of the troposphere".

His post, for the most part, is all word salad and makes no sense, whatsoever. For a start, the troposphere starts from around 6-10km above sea level. Wind can increase in speed as it funnels through valleys but it's hard to estimate whether or not this is the case in this example. A more concerning phenomenon around mountains is katabatic winds where, as warm air rises up one side of a mountain, the air is suddenly cooled as it travels up the mountain and then the cool air rushes down the other side of the mountain at incredible speeds - sailors are well aware of this - especially in the afternoons. I've seen, first hand the immense effects of katabatic winds whilst sailing in Greece and Croatia.

hallmark007 Posted at 2018-10-27 11:52
I think when flying in the mountains depending on which side of the mountain you fly, it can be very windy or very calm.

The speed and direction of the wind can be unpredictable in the uplands. As the moving air is pushed over a mountain range it is squeezed between the mountains and the top of the troposphere, causing the wind to speed up. It is nearly always windier, therefore, on mountain tops than in adjacent valleys. The wind is forced over ridges and through saddles, increasing in speed, and making these places more hazardous in stormy weather. The topography of the valleys and mountains often means the wind can be gusting, swirling about and rapidly changing direction, adding to the difficulties of keeping your balance and stability.

Nice piece of writing, but has nothing to do with my remark about a greek goddes.
Never mind, it is totally irrelevant....

Many happy landings is everebody`s goal !

cheers
JJB

gyrex Posted at 2018-10-27 23:35
His post, for the most part, is all word salad and makes no sense, whatsoever. For a start, the troposphere starts from around 6-10km above sea level. Wind can increase in speed as it funnels through valleys but it's hard to estimate whether or not this is the case in this example. A more concerning phenomenon around mountains is katabatic winds where, as warm air rises up one side of a mountain, the air is suddenly cooled as it travels up the mountain and then the cool air rushes down the other side of the mountain at incredible speeds - sailors are well aware of this - especially in the afternoons. I've seen, first hand the immense effects of katabatic winds whilst sailing in Greece and Croatia.

Hi,

I have learned that the troposhere starts not at 6 - 10k above dea level, "the troposphere starts from around 6-10km above sea level"

Copy Paste from wiki

The troposphere is the lowest layer of Earth's atmosphere, and is also where nearly all weather conditions take place. It contains approximately 75% of the atmosphere's mass and 99% of the total mass of water vapor and aerosols.[2] The average height of the troposphere are 18 km (11 mi; 59,000 ft) in the tropics, 17 km (11 mi; 56,000 ft) in the middle latitudes, and 6 km (3.7 mi; 20,000 ft) in the polar regions in winter.

The lowest part of the troposphere, where friction with the Earth's surface influences air flow, is the planetary boundary layer. This layer is typically a few hundred meters to 2 km (1.2 mi; 6,600 ft) deep depending on the landform and time of day.

cheers
JJB

AlansDronePics Posted at 2018-10-28 02:06
Yup, Keule is right. This little monkey lost his drone the same way.

[view_image]

sorry but that comment is super
as harsh as it is - sadly it's also true. so no offence for little smile ;) - but clearly a pilot error

gyrex Posted at 2018-10-27 23:35
His post, for the most part, is all word salad and makes no sense, whatsoever. For a start, the troposphere starts from around 6-10km above sea level. Wind can increase in speed as it funnels through valleys but it's hard to estimate whether or not this is the case in this example. A more concerning phenomenon around mountains is katabatic winds where, as warm air rises up one side of a mountain, the air is suddenly cooled as it travels up the mountain and then the cool air rushes down the other side of the mountain at incredible speeds - sailors are well aware of this - especially in the afternoons. I've seen, first hand the immense effects of katabatic winds whilst sailing in Greece and Croatia.

First up it was meant as a joke from a conversation between JJB , your good friend jumped in as he has some sort of fetish trolling me, something I know plenty about is weather and mountains and there was nothing wrong in what I said, I did not apply it to the op’s Case as you will have read my earlier post, or did you.

Wind, Rain and Snow
Warm air is lighter than cold air, so the air at ground level tends to rise, displacing the cold air at higher elevations, which falls. This creates convection currents throughout the troposphere, and they are more predominant at higher elevations, where the air is less dense and can move more freely. Consequently, winds are stronger at higher elevations. Colder temperatures at higher elevations also create precipitation, because cold air can't hold as much moisture as warm air. Moisture condenses out of the air as snow and ice, and it falls back to the ground. At lower elevations, where the temperature is warm, it turns to rain, but that doesn't happen at higher elevations where the temperature hasn't risen above freezing.

JJBspark Posted at 2018-10-28 01:56
Nice piece of writing, but has nothing to do with my remark about a greek goddes.
Never mind, it is totally irrelevant....

Ah well I think you should go back and read your post, shall I say it was not the best English you have ever written, so from what you wrote regarding what I said , I presumed you were saying that wind could not be a factor in OP’s loss of his drone.

hallmark007 Posted at 2018-10-28 02:30
Ah well I think you should go back and read your post, shall I say it was not the best English you have ever written, so from what you wrote regarding what I said , I presumed you were saying that wind could not be a factor in OP’s loss of his drone.

Wrong assumption, if you see my analysis wich shows that his MA could not return because of the wind.
True, english is not my native language. This  goddes takes revenge on mistakes people make on purpose.
This flight should not have flown, OP need to have more understanding of weather and drones, but imo it was not done deliberately wrong.

cheers
JJB

JJBspark Posted at 2018-10-28 02:11
Hi,

I have learned that the troposhere starts not at 6 - 10k above dea level, "the troposphere starts from around 6-10km above sea level"

If you were referring to nemesis the god, I wasn’t implying that it was retribution for flying in the wind, but we never know where our arch enemy will pop up and strike.

Sorry for your loss ...I feel your pain, lost one a couple of weeks ago albeit in different circumstances ...mine went into water but you have a chance of finding yours so best of luck

Its a big loss coming home without your drone and easy to feel disheartened. My advice is to get straight back on the horse man, buy another drone and fly it off another mountain, just heed the warnings.

Moving forward theres some good advice on here, you learn from your mistakes especially with an expensive drone.

hallmark007 Posted at 2018-10-28 02:41
If you were referring to nemesis the god, I wasn’t implying that it was retribution for flying in the wind, but we never know where our arch enemy will pop up and strike.

Yes, if Nemesis gets help form Thanatos....   omg, hide your drone!  

Kestrel Scot Posted at 2018-10-28 03:29
Sorry for your loss ...I feel your pain, II lost one a couple of weeks ago albeit in different circumstances ...mine went into water but you have a chance of finding yours so best of luck

Its a big loss coming home without your drone and easy to feel disheartened. My advice is to get straight back on the horse man, buy another drone and fly it off another mountain, just heed the warnings.

Have you been in touch with dji regarding loosing your drone?

hallmark007 Posted at 2018-10-28 04:13
Have you been in touch with dji regarding loosing your drone?

I haven't sent anything official anywhere ...unfortunately the drone is at the bottom of a loch (and literally) has no chance of re-surfacing

Kestrel Scot Posted at 2018-10-28 04:20
I haven't sent anything official anywhere ...unfortunately the drone is at the bottom of a loch (and literally) has no chance of re-surfacing

You really should sync your flight to dji cloud and start a case, while it maybe your fault I don’t know because of little details, on the other hand you still have a warranty in case of malfunction, if dji were to find you were at fault it is likely they will offer you 30% discount off a new MavAir, not sure if that’s something you might be looking for, but worthwhile getting your flight log checked out.
Good Luck.

A question for the seasoned pilot and yes I understand you never would have launched in such winds, but if you were caught in that situation would it be time better spent trying to descend and try to land somewhere better for recovery? New to drones so I'll use this as a teaching moment.

bbloomquist Posted at 2018-10-28 06:21
A question for the seasoned pilot and yes I understand you never would have launched in such winds, but if you were caught in that situation would it be time better spent trying to descend and try to land somewhere better for recovery? New to drones so I'll use this as a teaching moment.

Agree, but  that decision is a mental one....

First try to find a height wich less head wind and a height where its safe to fly (obstacles)
If you see "oops, i cannot make home" than make a decision to land somewhere safe using all the batt power left. Waiting to long result in a great drone falling out of the sky....

cheers
JJB

bbloomquist Posted at 2018-10-28 06:21
A question for the seasoned pilot and yes I understand you never would have launched in such winds, but if you were caught in that situation would it be time better spent trying to descend and try to land somewhere better for recovery? New to drones so I'll use this as a teaching moment.

It’s always better to lower altitude, you have all you need on your telemetry, if your in sport mode and pushing full forward, just check your speed against the ground your covering, MavAir flys at 45mph so if it’s loosing ground you can be sure wind is a lot stronger than aircraft speed.
Regards looking for somewhere to land. This is not something you should have to do when things go wrong, you should always take note of where your flying before you fly and take note of a couple of areas you could possibly land if you get into trouble, doing this you will find you will be less panicked when something goes wrong.
If you just take a few minutes preparing before you fly, you will fly with much more confidence.
Fly safe.

hallmark007 Posted at 2018-10-28 06:38
It’s always better to lower altitude, you have all you need on your telemetry, if your in sport mode and pushing full forward, just check your speed against the ground your covering, MavAir flys at 45mph so if it’s loosing ground you can be sure wind is a lot stronger than aircraft speed.
Regards looking for somewhere to land. This is not something you should have to do when things go wrong, you should always take note of where your flying before you fly and take note of a couple of areas you could possibly land if you get into trouble, doing this you will find you will be less panicked when something goes wrong.
If you just take a few minutes preparing before you fly, you will fly with much more confidence.

Good points! Thanks

bbloomquist Posted at 2018-10-28 06:46
Good points! Thanks

Here’s a preflight list,it’s for commercial but a lot applies to hobbyists.

https://forum.dji.com/forum.php?mod=viewthread&tid=119776

hallmark007 Posted at 2018-10-28 06:52
Here’s a preflight list,it’s for commercial but a lot applies to hobbyists.

https://forum.dji.com/forum.php?mod=viewthread&tid=119776

Awesome! Thanks hallmark007

hallmark007 - As the moving air is pushed over a mountain range it is squeezed between the mountains and the top of the troposphere, causing the wind to speed up.
hallmark007 - something I know plenty about is weather and mountains and there was nothing wrong in what I said,  


Except hallmark007 is spreading utter falsehoods about there being a squeezing effect between top of troposphere and mountains that results in an increse in wind speed.

Warm air is lighter than cold air, so the air at ground level tends to rise, displacing the cold air at higher elevations, which falls. This creates convection currents throughout the troposphere, ...

Credit for above goes to Sciencing: How Does Elevation Affect Weather?  (see section - Wind, Rain and Snow)

I think what Hallmark was suggesting is this http://xn--drmstrre-64ad.dk/wp-c ... ur/wres/speedup.htm when flying around large obstacle like buildings or mountains they can cause a tunnel effect where wind speed increases as the low of the air mass still need to equalise so it speed up, this can cause the updrafts and also what is known as rotor effect this happens when wind travelling at ground level is forced upwards by and obstacle (this happens quite alot around small airfields here in the UK south coast, you get a sudden rise in altitude on final which can catch you out if not paying attention and may also cause a stall if at low speed approach) if the op was flying around the valley it cold have been this tunnel effect that caused the drone to drift and no matter what stick input he tried it the wind was beyond the limits of the ship, the only thing the OP could have tried was reducing altitude and hope that the wind speed dropped enough to to rth or at least land.

the APP UAV Forecast is quite handy for windage but its also handy to know how far you are AMSL you are as normal aviaiiton charts can give an idea.

I would normaly do a quick up and down to see if she holds at height then decide to venture but do a quick test out and back to see how long it takes as this will gauge how much time you think you might have on a battery to still allow safe return inside your 30%

I feel sorry for the OP and hopefully he will find it.

Hope this helps or maybe ive just confused the situation more and if I have apologies

Schmooit Posted at 2018-10-28 10:16
I think what Hallmark was suggesting is this http://xn--drmstrre-64ad.dk/wp-content/wind/miller/windpower%20web/en/tour/wres/speedup.htm when flying around large obstacle like buildings or mountains they can cause a tunnel effect where wind speed increases as the low of the air mass still need to equalise so it speed up, this can cause the updrafts and also what is known as rotor effect this happens when wind travelling at ground level is forced upwards by and obstacle (this happens quite alot around small airfields here in the UK south coast, you get a sudden rise in altitude on final which can catch you out if not paying attention and may also cause a stall if at low speed approach) if the op was flying around the valley it cold have been this tunnel effect that caused the drone to drift and no matter what stick input he tried it the wind was beyond the limits of the ship, the only thing the OP could have tried was reducing altitude and hope that the wind speed dropped enough to to rth or at least land.

the APP UAV Forecast is quite handy for windage but its also handy to know how far you are AMSL you are as normal aviaiiton charts can give an idea.

Your correct, but my comment wasn’t regarding the OP’s incident, but rather to a comment made by JJB , but when your being trolled by a schizo, it seems any comment made , results in the need to continue trolling even if it’s at the expense of someone’s else’s thread.
Some really good tips there, thank you.

Hello Friends,Thanks everyone for all the quick responses, theories, concepts and guidance. I truly appreciate. Special thanks to JJBSPARK and KEULE for helping me out in tracing the approx search location and figuring out the root cause and sequence of events.

UPDATE:
Based on the approx. search location suggested by you all, i went today morning with 2 of my friends. The location is a large scale wheat farm land full of crop ready to be cut. We tried searching there for 2 hrs but couldnt continue it anymore as we were stopped by the land owners and farmers as they thought we might destroy the crops in the process. After explaining them the situation and my plight, they understood and told us that the crops were scheduled to cut by 24th Nov and if they find anything during this, they will inform us. We exchanged our numbers and had to leave the area empty handed
Lets hope that the drone could be found by someone and safely returned, without much damage. I decided that i will wait for another one month hoping for its return.

FINAL WORDS: Well as much as i am thankfull to everyone whoever took time to read my post and tried to help and comment immediately, i am also saddened by few trash talks made by some people. I totally agree that it was a bad decission and i dont know why i took such an amateaur decission but may be i was suppose to lose it and learn my lesson. I accepted this fact. But reading comments like "...monkey lost it" or "...it was MENTAL decission" disheartened me more. It was a expensive toy for me, a prized possession of mine and i made a wrong choice of flying it and i am repenting it but some people take this opportunity to laugh or comment or make fun of the situation. It was as if you come to somebody's funeral and make fun about the person that how he died, infront of his mourning relatives. Please think how am i be feeling now after losing such an expensive toy infront of my eyes, dissappearing in minutes, because of silly mistake.
@AlansDronePics: Not cool buddy. Not cool. Hope you never face such situation of losing your drone.
@JJBSpark: I am a frequent visitor of this forum and i truly admire your technical expertise wrt drones and your quality and prompt responses. When i posted this thread, i was actually praying that hopefully you will read my post and help me with your inputs and you did. I am deeply thankful to you for that... But didnt appreciate the use of words like "mental..." in some of your comments.


Anyways, thanks once again to all of you. Hopeing to see my drone in near future OR get a new and better one . May be god wanted me to get a better one than this ;) Adios friends.

Let's hope they see something shiny that day and stop the machinery in time

rolling56 Posted at 2018-10-28 11:14
Let's hope they see something shiny that day and stop the machinery in time

Ya i checked about that too.. Good thing is they use hand cutting techniques, they dont use any tractors or heavy machinery for cutting crops..so hopefully if its there they will find it easily without any problems.. Fingers crossed.

TechVoyager, I think you may have taken JJBsparks comment wrong I was asking from a seasoned pilots view what could have been done different, I am new to drones so anything helps. JJBspark said it would be a mental decision to either continue the path home or turn and try and land in a safe spot( no one can say what they would do until it happens to them) I didn't take it as him calling you mental. I sure hope the drone is returned to you, I think mine will fly away every time I launch it.

Bart

TechVoyager Posted at 2018-10-28 11:29
Ya i checked about that too.. Good thing is they use hand cutting techniques, they dont use any tractors or heavy machinery for cutting crops..so hopefully if its there they will find it easily without any problems.. Fingers crossed.

Do hope they find your drone and it is returned to you.

TechVoyager Posted at 2018-10-28 10:55
Hello Friends,Thanks everyone for all the quick responses, theories, concepts and guidance. I truly appreciate. Special thanks to JJBSPARK and KEULE for helping me out in tracing the approx search location and figuring out the root cause and sequence of events.

UPDATE:

if they find anything during this, they will inform us. We exchanged our numbers and had to leave the area empty handed

If you didn't, I would suggest offering them a Reward for finding and returning drone to you.  

HedgeTrimmer Posted at 2018-10-28 12:15
if they find anything during this, they will inform us. We exchanged our numbers and had to leave the area empty handed

If you didn't, I would suggest offering them a Reward for finding and returning drone to you.

Yes i already told them that i will reward them a good amount once they return it.

bbloomquist Posted at 2018-10-28 12:00
TechVoyager, I think you may have taken JJBsparks comment wrong I was asking from a seasoned pilots view what could have been done different, I am new to drones so anything helps. JJBspark said it would be a mental decision to either continue the path home or turn and try and land in a safe spot( no one can say what they would do until it happens to them) I didn't take it as him calling you mental. I sure hope the drone is returned to you, I think mine will fly away every time I launch it.

Bart

May be i am wrong...

Offering the reward was a good move now you have someone looking more than you could do by yourself, Good Luck on you MA reunion

That's a hard knot in you gut... Hope you find it.  Is it labeled with name?  

TechVoyager Posted at 2018-10-28 10:55
Hello Friends,Thanks everyone for all the quick responses, theories, concepts and guidance. I truly appreciate. Special thanks to JJBSPARK and KEULE for helping me out in tracing the approx search location and figuring out the root cause and sequence of events.

UPDATE:

I totally agree that it was a bad decission and i dont know why i took such an amateaur decission but may be i was suppose to lose it and learn my lesson.

Loss of a drone to high winds is possible even in non-mountain areas, relatively flat ground.  Where I normally fly, the wind can go from barely noticeable, to stiff wind with gusts between start of flight and middle.  You can check weather forecsts before hand, have plenty of flight experience, take precautions like flying into slight breeze, and still have mother nature through you a curve ball.  


When it comes to Weather forecasts, around these here parts, it is a running gag.  Weather Reporting - Only job where you won't get fired for being right only half time.

TechVoyager Posted at 2018-10-28 10:55
Hello Friends,Thanks everyone for all the quick responses, theories, concepts and guidance. I truly appreciate. Special thanks to JJBSPARK and KEULE for helping me out in tracing the approx search location and figuring out the root cause and sequence of events.

UPDATE:

Hi TechVoyager,

You understand my text completely wrong! Guesss is my bad english language.

Its a mental thing to make a good decision and choice in certain situations to land and not fly on and on and....
We all want our toy back, safe and sound with a normal landing in front of us. But if you make beforehand a decision what to do if this or this will happen, than its easier to act when "this" is happening!
So has nothing to do with mental when people are talking about mentally ill people etc etc.

As you probably have read more text from me on this forum you will know that i never judge people if something goes wrong. Only my fair opinion about what happend to their drones and sometimes advice what to do better.

Cheers
JJB

bbloomquist Posted at 2018-10-28 06:21
A question for the seasoned pilot and yes I understand you never would have launched in such winds, but if you were caught in that situation would it be time better spent trying to descend and try to land somewhere better for recovery? New to drones so I'll use this as a teaching moment.

A few things you could try:
Switch to Sport mode to provide more power to compensate for return headwind
Lower altitude of drone to see if it can make better return progress (done that several times)
If high wind is due to Funneling, first try flying at angle to move out of Funnel area, then try flying back to home
Start looking for a place to land drone that - gives you best chance of recovery and might serve as a wait-it-out spot.  As sudden as a wind comes up, it can also suddenly die down.

HedgeTrimmer Posted at 2018-10-28 09:34
Warm air is lighter than cold air, so the air at ground level tends to rise, displacing the cold air at higher elevations, which falls. This creates convection currents throughout the troposphere, ...

Credit for above goes to Sciencing: How Does Elevation Affect Weather?  (see section - Wind, Rain and Snow)

yeah, see #45    its an academic "law" to to inform others about your knowledge uh used sources ...

hallmark007 Posted at 2018-10-28 06:52
Here’s a preflight list,it’s for commercial but a lot applies to hobbyists.

https://forum.dji.com/forum.php?mod=viewthread&tid=119776

Great checklist Hallmark007, thanks for the link

Boffin Posted at 2018-10-28 15:52
Great checklist Hallmark007, thanks for the link

No problem I hope you get some use from it, many have used it, others have shorten it and used it as there own.
Fly safe.

Fly74 Posted at 2018-10-28 12:27
That's a hard knot in you gut... Hope you find it.  Is it labeled with name?

Yes labelled my name and contact details on the drone.