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A few Guidelines To Keep Pilots Airborne - Mike Mas

Mike Mas

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A few Guidelines To Help Keep Pilots Airborne - Mike Mas

Hey Guys - Had a little extra time, so I put together a few guidelines and tips on a variety of topics that seem to be a common problem. These tips will hopefully keep your machine in the air and safe - Enjoy!

Mavic’s Return To Home Feature - Without getting technical, the Mavic's “RTH” settings can be a bit confusing to a new pilot. In brief, every time your drone lifts off, it automatically marks that spot as a RTH GPS position so in an unlikely event it has to perform a RTH landing, those coordinates will be used to hopefully steer the machine back to the same launch area.

RTH Location Point may be Altered - There is two choices in the menu to mark where the machine will land in the event of a RTH protocol. They are; where the machine lifted off, or a different location that you choose. As an example, If you take off and decide to walk down the beach to another area to get a shot, you have the provision to “Re-Set” the RTH location to a position where “You Are” instead of where the machine lifted off.


Manually Selected Points are Not Dynamic - This means unlike other DJI aircraft, the Mavic will not follow the transmitter location automatically. Every time you move, you’ll have to re-mark your location if you want the machine to RTH to your new location.

Don't wait for a Crisis - To find out if your RTH will work. Even before your first manual RTH session, you’ll want to make sure all your setting are correct in the menus. If a RTH is activated, will the machine head home, hover or land. Also, the RTH altitude must be set to avoid tall trees, light poles, wires. You'll want to make sure these setting are correct.

When You feel Comfortable - Flying your machine and using the transmitters functions, you’ll want to test the RTH feature. Find a safe open area, fly off at a 200’ distance around 100’ high and activate the RTH. During your first few tries, keep you finger over the mechanical "Cancel / Stop" button on the left side of the trans display. If you feel something is not right, hit the cancel button and “Bail Out”, then manually fly back and try it again. Keep in mind, the protocol for RTH is based on the machine’s location and height when it is activated. While the drone might be located at a short distance from you, it “might” climb 100-200 feet before coming home, so don’t panic!

Powering “Off” your Transmitter - After you feel confident with manually activating the “RTH” and “Take-Off” features, you should “On Occasion” find an safe open area then fly the machine out 200’ from you and 100’ high in plain site, then power down the transmitter to activate a true “loss of signal” protocol. This is the only method that truly simulates a real life loss of signal and a GPS RTH. It’s better find out now, a few hundred feet from you that it works as expected, rather than testing it while the machine is a mile or so downwind. If it appears the drone is not following procedure, re-power the transmitter then after a few seconds, to be safe, tap the Cancel / Stop button on the left side of the trans display and manually fly back and re-check your settings.

Use the “Beginner Mode - The Mavic offers a beginner mode which limits the Drones distance and height from the pilot. This has a two-fold purpose. While its mainly for new pilots, it’s also useful when breaking in a new drone or after a repair just to make sure everything is working as it should. New Pilots should keep this feature activated for the first 20-30 flights since orientation and direction of a small drone that is grey in color is difficult to see, this feature will keep your machine in site.

Be aware of the Wind Direction and Speed - If you go out and its blowing hard, you should confine your flights to close-in distances. Also, keep the machine in a “Up-Wind” position from yourself. In just seconds, you can find your drone downwind and lose visibility. When this happens, a RTH will be your easiest option to get it back. Keep in mind, while it might be blowing 10-15 mph out of one direction close to the ground, it could be 10-15 mph or more in the opposite direction a few hundred feet up.

Get the Gear - The stock Mavic landing gear is poorly designed, not only is the camera and gimbal practically on the ground, so are the sensors and the downward looking cameras beneath the machine. It’s important to get yourself a $15 set of “Extended” landing gear for your Mavic. Keep in Mind, a RTH landing in most cases might not be exactly where you lifted off. One bad landing on some rocks either by the pilot or a RTH landing, may damage any of these sensitive components.

She’s Not Level - Making matters worse, the landing gear’s other design flaw is the fact the drone sits un-level on the pad, which hinders take-off and landings. If you examine the Mavic during a take off or landing, you’ll see the processor attempting to correct this un-level position by over compensating in pitch on take-offs, and momentarily re-lifting of the rear gear on landings in an effort to level the plane of the machine. I’m really puzzled what DJI was thinking with this gear set?


Camera Cover - Because of the poor landing gear design, DJI includes a protective clear plastic cover for the Mavic. I highly recommend that new pilots use the protective cover provided while you're learning to fly, or until you get the taller gear, as it will help protect the camera & gimbal.

Component Heat - The Mavic’s 24 cores of processing develops a lot of heat, so you’ll need be aware of different heat situations. As long as the machine is flying, its safe to use the camera cover since the down wash of air from the props provides more than adequate air flow over the fuselage and heat sinks. Of course, the cover should be removed for any serious video or still work. To avoid over-heating the circuity, always remove the camera cover if your sitting on the ground for more than a few minutes to allow the fan to move air from the fuselage more easily.

The Wrong Color - Another error is the Mavic's color, aside from being very difficult to see, with all the intense heat from the processors, there is now additional surface heat generated from the sun. In fact, sitting in direct sun light, the heat sinks on the bottom of the machine will become untouchable. If your doing any ground-adjusting for over a few minutes in summer, be sure the camera cover is off and if possible, move the machine to a shaded area to reduce the additional heat from the sun on the machines dark exterior.

Getting Pretty Pictures - If you’re new to drones, select either 720 or 1080P to save space and video record all your flights so in the event something happens, you’ll have a video record to analyze your whole session as well as what went wrong. Don’t worry about getting those risky shots and avoid any “people” shots as well. For now, concentrate only on the machine and what its doing.

Forget the 50% battery “Fly Back Home Rule” - If your machine is off at a distance on a mission, 50% battery might not get you back home. While the Mavic monitors; altitude, distance and remaining battery levels to activate an automatic RTH to prevent the battery from depleting on a flight back, it has no way of knowing what wind conditions the it might encounter during the flight. I've witnessed pilots losing their machine when they turned back home with 75% battery because of high wind conditions.

Air Speed will vary from Ground Speed - If the Mavic’s air speed is say; 30 mph, this does not necessarily mean its ground speed will be 30 mph. While the drone’s air speed will remain constant to the machines flight surfaces and fuselage, the speed and condition of the body of air around the drone will affect its ground speed.

Let’s say were at the Beach - We decide to fly out over the water to an Island say 3 miles off shore. Our drone is traveling at 30 mph and there is a 20 mph off shore tailwind to help us out, the drones ground speed will now be around 50 mph, at this speed it will take less than 4 min to reach the island.

On the Flight Back - Our drone’s airspeed is still 30 mph, but now it has to fight a 20 mph headwind to get home, our ground speed is now reduced to only 10 mph, so the trip back to the shore will now take around 18 minutes depending on gusts or around 4-5 times longer then our first leg of the Island trip.

This example helps to explain why we see so many posts from pilots who decide to range check their Mavic only to find out they can’t make it back on the battery and end up losing their machine. My best advise is to avoid these long range missions, they serve no purpose in the real world of drone flying.

Signal & Video Range - In a “Perfect World” the Mavic can travel 3-5 miles from the transmitter and return safely. However, there really is no “set range” you can count on since each location will be different with regard to interference, altitude, obstacles, conditions, wind and location. It’s important to note, a lot can (and will) happen during a round trip session that is unpredictable. We are led to believe that if anything happens to the transmitter link, the GPS will simply fly the machine back home, but this is not always the case. During a mission, we don’t know what towers or other transmitted RF, or GPS signal strength or interference our machine will have to encounter to complete its trip home. GPS RF signals are just as prone to interference as our transmit signals.

Transmitted Signal is “Line Of Site” - The further down-range we go with our model, the weaker the signal will be, so the transmit antennas position is of prime importance when the machine is at any distance. The transmit antennas radiate from their sides. Assuming we’re holding the transmitter / iPad level, when the machine is off at a distance in front of us, we’ll want the antennas angled slightly back towards the pilot so the sides of the antennas are scattering signal in a slight up-wards direction. Keep in mind, non directional antennas scatter signal to a very large area, so the signal is somewhat weak when compared to a P-Dish antenna which concentrates a stronger signal to a more confined area. Therefore, once the machine is out over a mile, there is “very little” signal actually captured by the drones antennas, making it very acceptable to other RF interference.
There is No Set Range - Every location will bear a different range based on your location, distance to the machine, your altitude and outside interference and temperature. Remember we’re sharing this frequency band with thousands of other applications, which are also captured by the drones antennas which have to be rejected to only see your transmitter signal. The drones range is affected by other metallic and non-metallic objects such as; obstacles, trees, buildings, power lines, etc. There may also be a reflected and delayed signal hitting the receive antenna at slightly different times to further confuse the receiver and reduce range.

Altitude is your Friend for Range - The higher the machine is away from obstacles the more direct signal it will receive. I’ve seen so many guys range check their machine 20-50 feet off the ground. Avoid flying at low altitudes when at any distance from the transmitter. Keep in mind low power home devices on adjacent frequencies have limited range, so your safer at higher altitudes where they cannot reach.

Practice - Practice - Practice - I cannot emphasize enough the importance of constant practice. A good habit is once your battery gets down to 60%, fly back to your general area and burn the rest of the pack doing close-in maneuvers that require you to fly, not the computer. Remember, It will take years of practice to be proficient with a drone if your planning on doing some “real projects”. Try to spend just as much time on the ground work as you do in the air. Avoid using the automated sequences to include take-off and landings.

Practice maneuvers such as precise approaches at different degree slopes, nose in, figure 8’s, backwards flight, etc. A common maneuver often used in production is a straight down vertical approach. In order for it to be smooth, your descent speed will have to be slightly less than the downward accelerated air, or the drone will fall into its own low pressure area. You’ll know when this happens since the machine becomes unstable and you’ll hear the props as they reach the disturbed air. This descent can be 2-3 times faster then normal by allowing the machine to plunge past its own low pressure area and back into clean undisturbed air. While the Phantoms can perform these quick drops maneuvers, the Mavic’s processor only allows the machine to descend at a much slower speed.

In Closing - I hope this overview provided a few answers to help keep your machine in the air!

Fly Safe - Mike Mas

www.rotory.com

gear.JPG
 
A few Guidelines To Help Keep Pilots Airborne - Mike Mas

Hey Guys - Had a little extra time, so I put together a few guidelines and tips on a variety of topics that seem to be a common problem. These tips will hopefully keep your machine in the air and safe - Enjoy!

Mavic’s Return To Home Feature - Without getting technical, the Mavic's “RTH” settings can be a bit confusing to a new pilot. In brief, every time your drone lifts off, it automatically marks that spot as a RTH GPS position so in an unlikely event it has to perform a RTH landing, those coordinates will be used to hopefully steer the machine back to the same launch area.

RTH Location Point may be Altered - There is two choices in the menu to mark where the machine will land in the event of a RTH protocol. They are; where the machine lifted off, or a different location that you choose. As an example, If you take off and decide to walk down the beach to another area to get a shot, you have the provision to “Re-Set” the RTH location to a position where “You Are” instead of where the machine lifted off.


Manually Selected Points are Not Dynamic - This means unlike other DJI aircraft, the Mavic will not follow the transmitter location automatically. Every time you move, you’ll have to re-mark your location if you want the machine to RTH to your new location.

Don't wait for a Crisis - To find out if your RTH will work. Even before your first manual RTH session, you’ll want to make sure all your setting are correct in the menus. If a RTH is activated, will the machine head home, hover or land. Also, the RTH altitude must be set to avoid tall trees, light poles, wires. You'll want to make sure these setting are correct.

When You feel Comfortable - Flying your machine and using the transmitters functions, you’ll want to test the RTH feature. Find a safe open area, fly off at a 200’ distance around 100’ high and activate the RTH. During your first few tries, keep you finger over the mechanical "Cancel / Stop" button on the left side of the trans display. If you feel something is not right, hit the cancel button and “Bail Out”, then manually fly back and try it again. Keep in mind, the protocol for RTH is based on the machine’s location and height when it is activated. While the drone might be located at a short distance from you, it “might” climb 100-200 feet before coming home, so don’t panic!

Powering “Off” your Transmitter - After you feel confident with manually activating the “RTH” and “Take-Off” features, you should “On Occasion” find an safe open area then fly the machine out 200’ from you and 100’ high in plain site, then power down the transmitter to activate a true “loss of signal” protocol. This is the only method that truly simulates a real life loss of signal and a GPS RTH. It’s better find out now, a few hundred feet from you that it works as expected, rather than testing it while the machine is a mile or so downwind. If it appears the drone is not following procedure, re-power the transmitter then after a few seconds, to be safe, tap the Cancel / Stop button on the left side of the trans display and manually fly back and re-check your settings.

Use the “Beginner Mode - The Mavic offers a beginner mode which limits the Drones distance and height from the pilot. This has a two-fold purpose. While its mainly for new pilots, it’s also useful when breaking in a new drone or after a repair just to make sure everything is working as it should. New Pilots should keep this feature activated for the first 20-30 flights since orientation and direction of a small drone that is grey in color is difficult to see, this feature will keep your machine in site.

Be aware of the Wind Direction and Speed - If you go out and its blowing hard, you should confine your flights to close-in distances. Also, keep the machine in a “Up-Wind” position from yourself. In just seconds, you can find your drone downwind and lose visibility. When this happens, a RTH will be your easiest option to get it back. Keep in mind, while it might be blowing 10-15 mph out of one direction close to the ground, it could be 10-15 mph or more in the opposite direction a few hundred feet up.

Get the Gear - The stock Mavic landing gear is poorly designed, not only is the camera and gimbal practically on the ground, so are the sensors and the downward looking cameras beneath the machine. It’s important to get yourself a $15 set of “Extended” landing gear for your Mavic. Keep in Mind, a RTH landing in most cases might not be exactly where you lifted off. One bad landing on some rocks either by the pilot or a RTH landing, may damage any of these sensitive components.

She’s Not Level - Making matters worse, the landing gear’s other design flaw is the fact the drone sits un-level on the pad, which hinders take-off and landings. If you examine the Mavic during a take off or landing, you’ll see the processor attempting to correct this un-level position by over compensating in pitch on take-offs, and momentarily re-lifting of the rear gear on landings in an effort to level the plane of the machine. I’m really puzzled what DJI was thinking with this gear set?


Camera Cover - Because of the poor landing gear design, DJI includes a protective clear plastic cover for the Mavic. I highly recommend that new pilots use the protective cover provided while you're learning to fly, or until you get the taller gear, as it will help protect the camera & gimbal.

Component Heat - The Mavic’s 24 cores of processing develops a lot of heat, so you’ll need be aware of different heat situations. As long as the machine is flying, its safe to use the camera cover since the down wash of air from the props provides more than adequate air flow over the fuselage and heat sinks. Of course, the cover should be removed for any serious video or still work. To avoid over-heating the circuity, always remove the camera cover if your sitting on the ground for more than a few minutes to allow the fan to move air from the fuselage more easily.

The Wrong Color - Another error is the Mavic's color, aside from being very difficult to see, with all the intense heat from the processors, there is now additional surface heat generated from the sun. In fact, sitting in direct sun light, the heat sinks on the bottom of the machine will become untouchable. If your doing any ground-adjusting for over a few minutes in summer, be sure the camera cover is off and if possible, move the machine to a shaded area to reduce the additional heat from the sun on the machines dark exterior.

Getting Pretty Pictures - If you’re new to drones, select either 720 or 1080P to save space and video record all your flights so in the event something happens, you’ll have a video record to analyze your whole session as well as what went wrong. Don’t worry about getting those risky shots and avoid any “people” shots as well. For now, concentrate only on the machine and what its doing.

Forget the 50% battery “Fly Back Home Rule” - If your machine is off at a distance on a mission, 50% battery might not get you back home. While the Mavic monitors; altitude, distance and remaining battery levels to activate an automatic RTH to prevent the battery from depleting on a flight back, it has no way of knowing what wind conditions the it might encounter during the flight. I've witnessed pilots losing their machine when they turned back home with 75% battery because of high wind conditions.

Air Speed will vary from Ground Speed - If the Mavic’s air speed is say; 30 mph, this does not necessarily mean its ground speed will be 30 mph. While the drone’s air speed will remain constant to the machines flight surfaces and fuselage, the speed and condition of the body of air around the drone will affect its ground speed.

Let’s say were at the Beach - We decide to fly out over the water to an Island say 3 miles off shore. Our drone is traveling at 30 mph and there is a 20 mph off shore tailwind to help us out, the drones ground speed will now be around 50 mph, at this speed it will take less than 4 min to reach the island.

On the Flight Back - Our drone’s airspeed is still 30 mph, but now it has to fight a 20 mph headwind to get home, our ground speed is now reduced to only 10 mph, so the trip back to the shore will now take around 18 minutes depending on gusts or around 4-5 times longer then our first leg of the Island trip.

This example helps to explain why we see so many posts from pilots who decide to range check their Mavic only to find out they can’t make it back on the battery and end up losing their machine. My best advise is to avoid these long range missions, they serve no purpose in the real world of drone flying.

Signal & Video Range - In a “Perfect World” the Mavic can travel 3-5 miles from the transmitter and return safely. However, there really is no “set range” you can count on since each location will be different with regard to interference, altitude, obstacles, conditions, wind and location. It’s important to note, a lot can (and will) happen during a round trip session that is unpredictable. We are led to believe that if anything happens to the transmitter link, the GPS will simply fly the machine back home, but this is not always the case. During a mission, we don’t know what towers or other transmitted RF, or GPS signal strength or interference our machine will have to encounter to complete its trip home. GPS RF signals are just as prone to interference as our transmit signals.

Transmitted Signal is “Line Of Site” - The further down-range we go with our model, the weaker the signal will be, so the transmit antennas position is of prime importance when the machine is at any distance. The transmit antennas radiate from their sides. Assuming we’re holding the transmitter / iPad level, when the machine is off at a distance in front of us, we’ll want the antennas angled slightly back towards the pilot so the sides of the antennas are scattering signal in a slight up-wards direction. Keep in mind, non directional antennas scatter signal to a very large area, so the signal is somewhat weak when compared to a P-Dish antenna which concentrates a stronger signal to a more confined area. Therefore, once the machine is out over a mile, there is “very little” signal actually captured by the drones antennas, making it very acceptable to other RF interference.
There is No Set Range - Every location will bear a different range based on your location, distance to the machine, your altitude and outside interference and temperature. Remember we’re sharing this frequency band with thousands of other applications, which are also captured by the drones antennas which have to be rejected to only see your transmitter signal. The drones range is affected by other metallic and non-metallic objects such as; obstacles, trees, buildings, power lines, etc. There may also be a reflected and delayed signal hitting the receive antenna at slightly different times to further confuse the receiver and reduce range.

Altitude is your Friend for Range - The higher the machine is away from obstacles the more direct signal it will receive. I’ve seen so many guys range check their machine 20-50 feet off the ground. Avoid flying at low altitudes when at any distance from the transmitter. Keep in mind low power home devices on adjacent frequencies have limited range, so your safer at higher altitudes where they cannot reach.

Practice - Practice - Practice - I cannot emphasize enough the importance of constant practice. A good habit is once your battery gets down to 60%, fly back to your general area and burn the rest of the pack doing close-in maneuvers that require you to fly, not the computer. Remember, It will take years of practice to be proficient with a drone if your planning on doing some “real projects”. Try to spend just as much time on the ground work as you do in the air. Avoid using the automated sequences to include take-off and landings.

Practice maneuvers such as precise approaches at different degree slopes, nose in, figure 8’s, backwards flight, etc. A common maneuver often used in production is a straight down vertical approach. In order for it to be smooth, your descent speed will have to be slightly less than the downward accelerated air, or the drone will fall into its own low pressure area. You’ll know when this happens since the machine becomes unstable and you’ll hear the props as they reach the disturbed air. This descent can be 2-3 times faster then normal by allowing the machine to plunge past its own low pressure area and back into clean undisturbed air. While the Phantoms can perform these quick drops maneuvers, the Mavic’s processor only allows the machine to descend at a much slower speed.

In Closing - I hope this overview provided a few answers to help keep your machine in the air!

Fly Safe - Mike Mas

www.rotory.com

View attachment 16397
Good post.
 
20-30 flights before turning beginner mode off? Too much. That definitely can't apply for everyone.
 
DJI should add this well thought out information to their 'Quick Start" manual...and I wanted to say THANK YOU for writing this...Wish I would have had this when I first received Merlin23.....but even after flying him for many months...there are still some great reminders written here...
 
I have been wondering how to simulate a loss of signal situation - thanks for making the suggestion about turning off the remote - duh...I should have thought of that.

Cheers!

David
 
Sorry, just can't bring myself to fit landing gear leg extensions, look fugly
 
Cool post, thanks!

With regards to cancelling a RTH, do you mean press the RTH button on the controller again to cancel it? Or do you mean press the red 'pause' button?
 
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