Drone Wind Data Project

Do you ever wish that your pibal could give you real-time wind data, straight to your phone?

 

Read the below article to find out how.

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Background

PiBalls are critical for balloon pilots to understand what the current wind direction and speed are at their launch site. Prior to balloon flights, a “Piball” (or Pilot Balloon) will be released. This is a helium filled balloon, which sometimes includes a small LED light, which when released, shows the pilots the general direction and speed of the wind. Forecasts are good for determining if we should wake up early or sleep in. PiBalls help determine a true Go/No-Go Decision at the launch site.

 

In 2019 I started researching using a drone to augment PiBall data. For a drone to fly level the onboard computer must determine which propeller to speed up or slow down throughout the flight. Many drone manufacturers, including DJI, include software that has the drone stop in place and fly level as soon as you let go of the controls. The idea was if we fly a drone straight up and straight back down, once the drone lands, (with a little bit of calculation,) we can see what propeller was spinning faster versus slower. In the flight log all this data is captured. This means that we can get wind speed, direction, and altitude from the drone flight. Now, the initial flight log is not readable initially without some work, for example below.

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As you can see the log isn’t readable by a person, it needs to be decrypted. Once decrypted the data results in a table, similar to the screenshot below. There are 52 other columns with data that can be used to calculate the data we need for the wind speed and direction.

DJI2.png

When I first started this project, I started to create a program to automatically decrypt the flight log and help with the wind calculation. In the middle of developing the program I upgraded my drone to the new DJI Mini 2 and I realized that every drone flight log is slightly different. Meaning, creating my own program would require me to buy every commonly used drone to support this effort. I then found the company AirData and their app UAV. AirData UAV was initially built to provide crash-prevention information and give pilots much broader data than typically captured in a logbook. The AirData UAV app is supported for Android and ISO devices. AirData currently supports over 70 different drones. A full list of supported aircraft can be found here: https://airdata.com/features#tab-panel-2

           AirData can take the flight log and generate a local wind profile at your launch site within 15 seconds of landing, including the wind speed direction and altitude.

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Per CFR Part 107 Drones are only permitted to fly up to 400’ (14 CFR Part 107 Small Unmanned Aircraft Systems. 107.51, The altitude of the small, unmanned aircraft cannot be higher than 400 feet above ground level, unless the small, unmanned aircraft:

  • Is flown within a 400-foot radius of a structure; and

  • Does not fly higher than 400 feet above the structure's immediate uppermost limit.

400 feet is enough data for takeoff and landing, but not enough for an actual flight. I fly in Florida and it is critical to make sure you will make it over the swamp into a suitable landing area, and those upper winds are key when planning a flight. I had significant concerns with how accurate the drone wind data was, so after significant testing, I would put the drone up before each flight and then complete my balloon flight and compare the Digitool flight path for my flight up to the 400 foot mark. I found that the wind speed and direction and altitude from the drone wind collection was within 3 degrees and less than one mile an hour difference then my actual flight path. 9/10 flights the drone data was spot on. The 1 outlie flight was due to weather that rapidly changed after sunrise.

I was confident that I now could collect enough data. The next big issue was 400 feet of data is not sufficient for the actual flight and to truly supplement the PiBall data I needed 1500 feet of data (at least).  This is where the 19-month long process started with getting a waiver approved from the FAA to go to 1500 feet. Most FAA waiver information I could find online dealt with flying over a distance, and I only wanted to fly the drone straight up to 1500 feet and straight back down, so there was months of back and forth with the FAA. Drone waivers are submitted through https://faadronezone.faa.gov, and the web interface has been updated in the last two years so the site walks you through what waivers need to be submitted but the site does not guide you through the safety justification, which is the piece that the FAA uses to approve or deny your waiver.

In order to complete your drone operation there are two waivers you must submit and they can be submitted together, 107.31 & 107.51b.

14 CFR § 107.31 (Visual Line of Sight Aircraft Operation)**

14 CFR § 107.51 (b) (Operating Limitations: Altitude)*

For each waiver you must provide proper safety justification for each area specified in this following document: https://www.faa.gov/uas/commercial_operators/part_107_waivers/waiver_safety_explanation_guidelines/media/WSEG_operational_risks_mitigations.pdf

When you submit a waiver, you can submit for lengths of time from one day to four years. Crafting a 4-year waiver that the FAA will approve requires some time and patience. You will not be able to straight copy and paste the waiver template I am providing; each fly area is unique. You may have to submit multiple waivers before you get your official approval. It is up to each remote pilot to prove that your drone operation can be accomplished safely in your given fly area. To give you an idea, I submitted over 12 waivers with over 170 pages of documentation over 19 long months before I received my first approval. I've been asked several times if I'd like to monetize this process, that is not my intention. My intention is to help the balloon community become safer and help pilots make a better Go/No Go decision.

Any pilot that wants to gather the same type of data with a drone can reach out to me and I will help guide you through the process and deal with some of the hurdles with submitting drone waivers. I want to thank Laurie Spencer with the Spirit of Boise Balloon Classic. She and her event saw the value in my process and encouraged me to gather the data at her event. I was able to gain a FAA waiver approval for the event and collected drone data each day and compared it with the on-field meteorologist’s information. On the third day of the event the meteorologist said there was no way to box the field during brief, but with the drone data almost every balloon boxed the field.

 

The Process

The cost of my personal equipment follows. My total set up costs $404.96

Drone - $299.99

DJI Mini SE

LINK 

Lights- $74.99 +$26.99

Strobon 3 Pack Cree Navigation Battery Operated Strobe Lights for Drones

Link
1 White Flytron Strobon Cree by Strobe Light for Drones DJI Mavic Phantom
link

App - $2.99/month

Airdata subscription link 

HD 360 LITE
 

To begin the process, review the waiver template 14 CFR § 107.31 and 14 CFR § 107.51 (b) and Operation Parameters Safety Justification. You will need to read through each document and update them accordingly. I have gone through the document and highlighted most of the areas you must change but before you submit to the FAA you will want to read through the entire document and make sure all the stated facts are accurate. Once a waiver is submitted it will take at least 30 days before you will get a response. If there is something incomplete or incorrect in your waiver and it is returned, you’ll have to resubmit and wait another 30 days. Once you have reviewed all three documents and updated them for your flight area you are ready to register and submit your waiver.
 

You will need to register for an account at faadronezone.faa.gov. Once you have an account you will need to register your drone in the same portal. At time of writing this there was a 1x charge for $5.00 to register the drone.
Now you are ready to create and submit the waiver.

 

My first waivers came back denied because of something I forgot to change or some safety criteria that was not included in specific fly area.  If your waiver is denied, you will receive a generic letter from the FAA drone zone team that gives you a general idea of why they denied it. I recommend calling and talking to one of the analysts and have them review the notes that were left by the approving authority, because they can tell you which of the numbered question answers you need to modify or change.

 

In my experience on average, it takes about 30 to 40 days for the FAA to review and deny the waiver, and when they were going to approve it took about 50 days from submission. The analysts at the contact center for drone zone are extremely helpful and they want to help you get your waiver approved. Please be patient with them and ask as many questions as you need to understand what you may be missing.

 

Post Waiver Approval

Once you receive an approved waiver, depending on your flight area, you may also need to submit for an airspace authorization. That process is extremely quick as long as you already have an approved drone waiver.  24 hours before each drone operation covered under the waiver you will need to submit a notice to airmen (NOTAM). The quickest way I have found is via the weather services website. The site has a tool for you to enter your information, and you can do it up to 30 days in advance. There is a simple clone and submit feature where all you have to do is change the date after you have filled it out once. The NOTAM must be submitted 24hr in advance before each flight. In order to use the drone with how I have specified the waiver you will be required to get your remote pilot certificate. if you already are a private or commercial pilot it's extremely easy to add your remote pilot certificate visit, you can learn more here: https://www.faa.gov/uas/commercial_operators/become_a_drone_pilot/#ech

Existing Part 61 Certificate Holder’s Requirements for Remote Pilot Certificate:

  • Must be easily accessible by the remote pilot during all UAS operations

  • Certificate holders must complete an online recurrent training every 24 calendar months to maintain aeronautical knowledge recency

Now that you have an approved waiver and your pilot certificate you can complete your wind data collection and share it with other pilots in the area to help them make a GO/No Go decision. if you have any questions or issues with submitting the waiver or the process please email me airhoundfl.@gmail.com.

 

Jeff Thompson over at hotairballoonist.com has created a video tutorial. How to collect the data based on my process. http://hotairballoonist.com/Video/MavicScreenVid.mp4

DON'T used the HD sync App it is no longer supported by Airdata and isn't needed. 

Check out this video how to setup an auto upload from the airdata app so all you have to do is open the app.

Android LINK

IOS LINK


 

The 2 waivers below are only templates and I have highlighted sections that you will need to update based on your fly area. {lease read all the waivers fully because some things may also need to be corrected based on your flight location. Just because I have had these waivers approved for my area does not mean yours will be approved without extensive review by the FAA. Click on the waiver number to download.