Aerial Thermal Infrared (UAV-TIR)

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Jan 6, 2017 - operation (up to July 2015); that include flying at 259 meters high / 1077 meters far, flying over the sea, flying .... Kite aerial thermography (KAT).

Aerial Thermal Infrared (UAV-TIR) 無人機 熱紅外 技術 SGD research system Edited by Alan Kwok January 6, 2017 Introduction With UAV-TIR, I completed a breakthrough Aerial Thermal Infrared SGD research task on Feb. 11, 2015 (“DIY research system: IR-UAV mission” We have two UAVs (Drone / Quadcopter): [Phantom-GoPro] with camera and [Phantom-Tau] with IR camera. Such setup just cost about HK$45,000. Since March 2014, I have completed almost 50 flights with related operation (up to July 2015); that include flying at 259 meters high / 1077 meters far, flying over the sea, flying at night, etc.


This record logged most of my development details and related finding.

[Phantom-Tau] FLIR IR camera + Mini SD card Video Recorder


Tau 2 IR Camera with Starter Kit (46336013H-FPNLX, TAU2 336, 13mm-f1.25 FPNLX Serial numbers: 86794)

First Person View System

Phantom 1. 2. 3. Why bought it

Mini SD card Video Recorder (DVR as Flight Data / IR Video Recorder)

Operation (Phantom) Before flight: 1.

2. 3. On Screen Display (Flight Data)



Flight training (knowledge, professional instruction and practice); Understand On Screen Display, Local Guidelines for UAS. In Ready to Fly (non-GPS) status, only height limit works and the flying height restricted to be not over 120m. Site environment - Weather criteria (Visibility, Cloud ceiling, Wind speed; Thunderstorm, Rain or Strong Monsoon). Batteries (GoPro, PHANTOM + Remote Controller, FPV) are fully charged. * Never plug or unplug the battery into the aircraft when it is powered on. “2200mAh 3S LiPo - 2.2A, 11.1V (3S)” - Press START/ENTER key for more than 3 seconds to start charge. Learn from error: *** Night-Flight unexpected landing problem / crash: the drone going down @ TK, when my eye move to landing area (I face land instead water) from FPV monitor, I saw nothing (Ground, Plant and Eddie = dark completely!) … *** Pilot has to face water instead land when landing to avoid lost sight @ dark *** IR Sea Water Surface Searching:  Do search at night (no sun effect & minimums ship traffic), low humidity (help to get clear IR image)  Do search at longest tide station period (minimize surrounding flow current effect)  Do search at lowest tide period (water surface closer discharge outlet – bigger temperature difference be easier detected)  Phantom-Tau scanning capacity (Area per battery) = about 200m X 500m @ about 105m height

Flight (Phantom-GoPro):

Flight (extra info. for Phantom-Tau):


1. 2. 3.


3. 4.


6. 7. 8.






Flight route plan (Home-point and other interesting key points) Always fly >3m away from person and any obstacles, high-voltage lines. System Check: Camera (GoPro / FLIR + DVR) condition and settings. Gimbal - installed firmly PHANTOM propellers, motors, batteries, cables, compass module, antenna are in good condition. Do not fly with aging or broken parts. HERO3+ Settings: Ultra Wide [Field of View] - Video resolution = 1920x1440p 24 fps (Photo dimension = 12M) + Simultaneous Video and Photo = 5 seconds; Set up = One Button Ground system (Controller + FPV + DVR + Battery) setup Remote Controller: S1 (R) and S2 (L) switches @ the upper most position (1), all sticks are at mid-point, then Power ON (LED solid on = functioning normally). Takeoff - Switch on the remote controller first, then the multi-rotor. After landing - Power off the multi-rotor first, then the remote controller. Compass Calibration: * Carry out the calibrating procedures for the first flight in new field. Toggle the S1 (R) back and forth 5 times (from position 1 to 3) enter into compass calibration mode. LED = Yellow Rotate aircraft horizontally (Aircraft Nose = Pilot Nose) and 360∘(counter clockwise) LED = Green Turn aircraft vertically (Nose - Ground) and 360∘Rotate (counter clockwise) Propellers = Install … Camera = ON *Make sure power on the camera before DVR PHANTOM 2 on the ground (Battery level indicators facing pilot, align PHANTOM front and EYE front). PHANTOM 2 battery = ON (Press 1 time + Press 2 seconds). Gimbal self-testing: After initializing, camera lens will point to aircraft nose direction. During Test - Keep the power-on gimbal system still and horizontally. LED flight indicator blinks green/yellow (non-GPS) = Ready to Fly mode. Takeoff: Waiting for “GPS” mode / Green lights. CSC command [L] LR + [R] LL (MUST @ those corners) > motors have spun up > release both sticks simultaneously. L^ (throttle) only (Straight Up) – Slowly to lift the aircraft off the ground (about 2M high) … Hovering over a level surface … FPV (Ground Monitor) = ON Press “function” before power off DVR or fail recording. OSD (Battery > 30%, Distance < 1000m) Prepare Landing: Drive Phantom to suitable location (Hovering about 2M high). Camera Lens to front (avoid damaged by ground objects). Landing: Lv (throttle) only (Straight Down) - Gently to descend and land … keep the stick (throttle) at its lowest position after landing for about 3~5 seconds which will automatically stop the motors. Regaining Control during Failsafe Procedure: S1 (R) switch @ position 2 / 3. If remote controller’s signal is recovered, control is returned back to the pilot.


Make sure the TF card of the DVR (Tau2) is in place. Remove Camera Tau2 lens cap before Power ON Phantom. Power ON the FPV after Phantom took off, and presses the “function” key before power off DVR. Otherwise, the DVR may fail recording. Press “Function Key” first (DVR of Tau2), then Power OFF PHANTOM 2 battery.

Note 1.

A tricky way overcome takeoff problem @ Phantom-GoPro (20150428) - Do Not follow the normal Takeoff Procedure; and start motor @ “0” satellite acquired instead.



Up to 2 years imprisonment for negligent UAV operation crime (疏 忽操作航空器罪, 最高可判監 2 年) 015-ccm-07_w.mp4 The arrival / departure flight paths (HKIA)


Phantom 2 flight limits


Meteor seems be recorded when I was testing our IR system (point to an airplane @ Shatin 11:46:38, 11:46:49 About 1/60 second, Unknown Object @ 11:46:38 flied over lower right corner.

cameras strapped to their chest.

About 1/30 second, Unknown Object @ 11:46:49 flied from right to left.

Further study Use “ThermalCapture” instead current “Mini SD card Video Recorder” ( [email protected])

As UAV-TIR systems require a lot of tailor made parts, how 3D design and 3D printing benefit create such parts will be our study topic.


One of the earliest uses of unmanned aircraft taking aerial photographs was in World War II when the Germans experimented with pigeons specially trained for the aerial missions using 40-gram

Acknowledgements ! I put remark here to commemorate my mother Wong Yuet Wan as I can do nothing when she is in serious condition in Canada except continue this record writing. Thank you for my sister May Kwok …

Reference My IR videos at Sha Tin Hoi taken on Mar. 19, 2015:,, Other user videos: FLIR practice, Flying over a landslide, Supplier videos: FLIR Thermal TAU 320 Flight Test,, DJI videos: Flying Over the Crescent Moon Spring in China, Tian Shan Mountain in China, The Highest TV Tower in China, Phantom @ altitude 2425ft 9pQAw, Supplier / Service Provider:,,,,,,, Info:,, New techniques reveal the importance of groundwater seeping into the sea “The thermal camera used is a FLIR Tau 640 attached to a DJI Phantom Quadcopter.” Detecting Caves with Thermal Imagery within Ka’a’awa Valley Investigating Near-Shore Submarine Groundwater Discharge (SGD) in the Ka’a’awa Valley Phantom @ Student’s field trip Aerial "hexacopter" gives geography research a lift Riverwatch uses robotic symbiosis to study waterways cribers&utm_campaign=8bdf0d4fbf-UA-22353604&utm_medium=email&utm_term=0_65b67362bd-8bdf0d4fbf90864213 Aerial Thermography - detect subsurface archaeological features How aerial IR can be used as a NDT Tool for Asset Management

Kite aerial thermography (KAT) Remote Sensing (Airborne imagery):,, Flying Drones Are Mapping New Oil Reserves In Norway FLIR movie of water:,, Using Thermal Imaging to Detect the Ogden Utah Hot Springs in the Ogden Canyon Ogden Utah Hot Springs Infrared Re-inspection Environmental Remote Sensing Advances in Selected Applications and Methodology for Aerial Infrared Thermography Surveying and Aerial Reconnaissance using Draganflyer UAV Helicopters and ImageJ Software Evaluating Nutrient Fate and Redox Controls in Groundwater in Riparian Areas Thermal Imaging Camera Use: Identifying Groundwater Inputs to a Reef in American Samoa, Fish-Population Dynamics Study by USGS Leetown Science Center, Brook Trout Restoration Activities by the USGS Virginia Water Science Center Submarine groundwater discharge: identification and quantification via remote sensing, hydrologic sampling, and geochemical tracers Assessment of submarine groundwater discharge by handheld aerial infrared imagery: case study of Kaloko fishpond and bay, Hawai’i (T. Ka’eo Duarte, Harold F. Hemond, Donald Frankel, Sheila Frankel) Low-Cost UAV-Based Thermal Infrared Remote Sensing: Platform, Calibration and Applications (Hu Sheng, Haiyang Chao, Cal Coopmans, Jinlu Han, Mac McKee, YangQuan Chen) Dense Point Cloud Extraction from UAV Captured Images in Forest Area (Wang Tao, Yan Lei, Peter Mooney) A UAV based system for real time flash flood monitoring in desert environments using Lagrangian microsensors (Mohamed Abdelkader, Mohammad Shaqura, Christian G. Claudel and Wail Gueaieb) Airborne Thermal Data Identifies Groundwater Discharge at the NorthWestern Coast of the Dead Sea (Ulf Mallast, Friedhelm Schwonke, Richard Gloaguen, Stefan Geyer, Martin Sauter, Christian Siebert)

Aerial infrared imaging reveals large nutrient‐rich groundwater inputs to the ocean (Adam G. Johnson, Craig R. Glenn, William C. Burnett, Richard N. Peterson, Paul G. Lucey)

Multispectral Remote Sensing from Unmanned Aircraft: Image Processing Workflows and Applications for Rangeland Environments (Andrea S. Laliberte, Mark A. Goforth, Caitriana M. Steele, Albert Rango)

The Design and Testing of a Procedure to Locate Fresh Submarine Groundwater Discharge in Cyprus (Kathryn M. Olesnavage)

Seismically active area monitoring by robust TIR satellite techniques: a sensitivity analysis on low magnitude earthquakes in Greece and Turkey (R. Corrado, R. Caputo, C. Filizzola1, N. Pergola, C. Pietrapertosa, V. Tramutoli)

Thermal infrared detection of submarine springs associated with the Plymouth Limestone (I. S. ROXBURGH)

REMOTE SENSING APPLICATIONS to GROUNDWATER (A.M.J. Meijerink) AIRBORNE INFRARED THERMOGRAPHY FOR ENVIRONMENTAL AND FACILITY MANAGEMENT OF THE ARMY NATIONAL GUARD TRAINING FACILITIES (Qassim A. Abdullah, Richard McClellan) Using Thermal Infrared Imagery (TIR) for Illustrating the Submarine Groundwater Discharge into the Eastern Shoreline of the Dead Sea-Jordan (Emad Akawwi, Abdallah Al-Zouabi, Maher Kakish, Fredrich Koehn, Martin Sauter) Autonomous Aerial Water Sampling (John-Paul Ore, Sebastian Elbaum, Amy Burgin, Carrick Detweiler) Band-reconfigurable Multi-UAV-based Cooperative Remote Sensing for Real-time Water Management and Distributed Irrigation Control (Haiyang Chao, Marc Baumann, Austin Jensen, YangQuan Chen, Yongcan Cao, Wei Ren, Mac McKee) DETERMINATION OF THE UAV POSITION BY AUTOMATIC PROCESSING OF THERMAL IMAGES (Wilfried Hartmann, Sebastian Tilch, Henri Eisenbeiss, Konrad Schindler) Evaluation of Geophysical and Thermal Methods for Detecting Submarine Groundwater Discharge (SGD) in the Suwannee River Estuary, Florida (Matthew Weiss) Finding Pollution with Aerial Infrared Thermography (Gregory R. Stockton) Ground-based thermography of fluvial systems at low and high discharge reveals potential complex thermal heterogeneity driven by flow variation and bioroughness (M. Bayani Cardenas, Judson W. Harvey, Aaron I. Packman, Durelle T. Scott)

Some modern techniques in hydrogeology (Haefeli, Charles) UAV BORNE MAPPING SYSTEM FOR RIVER ENVIRONMENT (Masahiko NAGAI, Tianen CHEN, Afzal AHMED, Ryosuke SHIBASAKI) Band-reconfigurable Multi-UAV-based Cooperative Remote Sensing for Real-time Water Management and Distributed Irrigation Control (Haiyang Chao, Marc Baumann, Austin Jensen,YangQuan Chen, Yongcan Cao, Wei Ren, Mac McKee) SUBMARINE GROUNDWATER DISCHARGE: UNDERSTANDING FLUX SIGNATURES IN THERMAL INFRARED DATA IN PORT JEFFERSON AND STONY BROOK HARBORS, LONG ISLAND, NEW YORK (Joseph Tamborski) EVALUATING THE SENSITIVITY OF AN UNMANNED THERMAL INFRARED AERIAL SYSTEM TO DETECT WATER STRESS IN A COTTON CANOPY (D. G. Sullivan, J. P. Fulton, J. N. Shaw, G. Bland)

Term (UAV): BVR Flight = Beyond Visual Range Flight CHDK = Canon Hack Developer Kit allows you to run special firmware on an SD card instead of the camera’s native firmware. It gives all sorts of additional functionality (depending on model), including the ability to run scripts (basic and lua) such as an intervalometer. CMU = Camera Multi Unit, which is used for camera functions control. CSC = Combination Stick Commands


ESC = Electronic Speed Control

High resolution aerial and field mapping of thermal features in Ragged Hills, Yellowstone National Park (Juliane Becker)

GCP = Ground Control Point

High-resolution aerial infrared mapping of groundwater discharge to the coastal ocean (Jacque L. Kelly, Craig R. Glenn, Paul G. Lucey) Infrared Object Detection & Tracking in UAVs (Frederik Stendahl Leira) System Design of an Unmanned Aerial Vehicle (UAV) for Marine Environmental Sensing (Joshua Leighton) Localization of lacustrine groundwater discharge (LGD) by airborne measurement of thermal infrared radiation (Jörg Lewandowski, Karin Meinikmann, Thomas Ruhtz, Franziska Pöschke, Georgiy Kirillin) Non Military UAV R&D in Asia (ATIP/Asia) Remote sensing of environment on the base of the microavition (V.I. Binenko, V.L. Andreev, R.V. Ivanov)

FPV = First Person View

GCU = Gimbal Controller Unit GPS = Global Positioning System IMU = Inertial Measurement Unit (gyroscope, accelerometer, magnetic sensor) INS = Inertial Navigational System IOC = Intelligent Orientation Control iOSD = On Screen Display MC = Main Controller MVS = Multi View Stereo PMU = Power Management Unit

RX = Video Link Receiver SFM = Structure From Motion TX = Video Link Transmitter UAV = Unmanned Aerial Vehicle UATCS = Unmanned Aircraft Thermal Camera System (@ HKU ESD)

Term (FLIR): AGC = Automatic Gain Control FFC = Flat field correction LUT = Look-Up Table ROI = Region of Interest

Term (Remote sensing): DEM = Digital Elevation Model DTS = Distributed Temperature Sensing FO-DTS = Fiberoptic Distributed Temperature Sensing LGD = Lacustrine Goundwater Discharge LIDAR = Laser Imaging, Detection and Ranging NDT = Non-Destructive Testing SGD = Submarine Groundwater Discharge SST = Sea-Surface Temperature TIR = Thermal Infrared

Other: DSP = Digital Signal Processor HOV = Human-Occupied Vehicle

Appendices A Civil Aviation Department - Guidelines on Operations of Unmanned Aircraft Systems (UAS) Introduction With the advent of aviation technology in recent years, Unmanned Aircraft Systems (UAS) are widely used, mainly for military purposes, in many parts of the world. There are also a growing number of civilian applications of UAS, e.g. aerial surveillance, photography, and search and rescue. With the maturing and miniaturisation of applicable technologies, UAS offer possibilities for cheaper, more capable alternative airborne equipment that can be used without risk to aircrew. Civil Aviation Department (CAD) is responsible for processing applications for non-recreational operations of UAS (such as for hire or reward) within Hong Kong. With the significantly different level of sophistication of UAS available in the market, any person intending to operate UAS, regardless of size and weight, for non-recreational purpose within Hong Kong should submit details to CAD well before the intended date of operation. Flying Unmanned Aircraft Systems (UAS) weighing not more than 7 kg (without its fuel) for recreational purpose can be classified as model aircraft flying, and no application to CAD is required. For details, please refer to the webpage on "Flying Model Aircraft" ( Except with CAD's endorsement, heavy UAS weighing more than 7 kg (without its fuel) are not allowed to fly in Hong Kong for recreational purpose. The following are the general operational parameters for safe operations of non-recreational UAS: 1. Area of operations a) UAS shall normally not be flown within the Aerodrome Traffic Zone (ATZ) or within 5 km of any aerodrome. b) UAS shall not be flown over or within 50 m of any person, vessel, vehicle or structure not under the control of the UAS operator; except that during take-off and landing, the UAS must not be flown over or within 30 m of any person other than the person in charge of the UAS or a person necessarily present in connection with the operation of the UAS. Further conditions on flight safety clearance may be imposed on the operation of the UAS as necessary. c) The UAS operation site (including emergency operation zone and any safety zone for the operation of the UAS) shall be under the operator's full control. d) The take-off and landing area should be properly segregated from public access. 2. Control of UAS The UAS operator shall be on site and keep the UAS within Visual Line of Sight (VLOS) during the period of the flight. Operating within VLOS means that the UAS operator is able to maintain direct, unaided (other than corrective lenses) visual contact with the UAS, and is able to monitor the UAS flight path in relation to other aircraft, persons, vessels, vehicle and structures for the purpose of avoiding collisions. 3. Other related issues a) The UAS operator is responsible for ensuring that no person and property would be endangered by the UAS, and shall not fly the UAS unless he has reasonably satisfied himself that the flight can be safely made. b) No hazardous material may be carried nor objects be dropped from the UAS in order to avoid endangering persons or property on the ground. c) The person in charge of the UAS shall not fly the UAS unless before the flight he has satisfied himself that the mechanism that causes the UAS to

home and land in the event of a failure of or disruption on any control systems, including the radio link, is in working order. d) The UAS operator shall maintain records of each flight made pursuant to the permission and makes such records available to CAD on request. e) A site safety assessment has been completed by the UAS operator, and can be made available to CAD on request. f) Permission of the land/property owner on whose land/property the UAS is intended to operate has been obtained. g) The operation is carried out in accordance with the operations manual submitted to CAD. 4. Altitude of Operations The altitude of UAS shall not exceed 300 feet above ground level. 5. Altitude keeping performance capability The UAS operator shall describe the means of altitude keeping to ensure that the actual altitude flown is accurate. 6. Time of Operations a) UAS operations shall be conducted during daylight hours only. b) No more than one UAS will normally be permitted at any one time within the same block of designated airspace. 7. Weather Criteria a) ground visibility of not less than 5 km - visibility of more than 5 km may be required depending on the nature and area of operations; b) cloud base not lower than the approved altitude of operations; c) surface wind of no more than 20 knots, unless otherwise specified by the manufacturer (the surface wind speed limit may be reduced if the controllability of the UAS is in doubt); d) the UAS operator shall have a hand-held anemometer to monitor surface wind speed on site; and e) the UAS operator must not launch the UAS when Rainstorm Warning, Tropical Cyclone Warning or Strong Monsoon Signal is in force. 8. Pilot Qualification Evidence of pilot competency is required when making an application for permission to operate UAS but currently there are no pilot licences for the operation of UAS. CAD accepts Basic National UAS Certificate – Small Unmanned Aircraft (BNUC-S) or equivalent for evidence of UAS pilot competency. 9. Operations Manual a) The UAS operator is required to submit an operations manual covering the procedures to be followed for all envisaged operations of the UAS. This document is a key requirement to enable CAD to accurately assess the application and the safety case before deciding whether to grant a permission. b) Guidance for the compilation of the UAS operations manual can be downloaded ( df). 10. Communication with ATC a) The UAS operator shall inform the CAD/Aerodrome Supervisor before launching and on completion of the UAS operation. b) The UAS operator shall provide his/her contact phone number to the CAD/Aerodrome Supervisor, who may instruct to stop the operation when necessary. 11. Frequency spectrum and Radio Frequency Interference (RFI) The UAS operator is required to seek approval from the Office of the Communications Authority on the use of radio frequencies and to ensure that no RFI is caused to air traffic operations and air navigation equipment. Appendices B Civil Aviation Department - Flying Model Aircraft Flying Model Aircraft Safety in Radio-Controlled Model Aircraft Flying

Beware of the danger

Choice of flying sites

Flying radio-controlled model aircraft can be a rewarding and enjoyable pastime. However, such aircraft can also pose a serious safety problem to operational aircraft.

A good choice of flying site not only minimises the possibility of an accident but also enhances the pleasure of the flying experience. Here are some tips to help you choose a good site. A good site should be:

There are incidents in which flying model aircraft in the vicinity of main flight paths have endangered the safety of helicopters operating there.

(i) clear of persons, vessels, vehicles or structures; (ii) away from helicopter landing pads;

Operator of radio-controlled model aircraft should appreciate that the limited airspace over Hong Kong is shared by all aircraft. Helicopters, for operational reasons, may fly close to the tops of hills and mountains, at low level and at high speed.

(iii) clear of any power sources such as power lines, transformer stations, pylons, and transmitter towers, etc which might cause radio interference;

It is difficult for a pilot to see and identify a model aircraft until he is at close quarters, when it may be too late for evasive action. The result of a collision can be disastrous.

(v) free from visual obstruction, so that the operator can see the model aircraft in flight at all times.

(iv) flat enough to enable safe take-off and landing; and

It is therefore imperative that model aircraft operator flies his model at a height not exceeding 300 feet above ground level, keep a watch for any aircraft flying in the vicinity and ensure that he lands his model immediately when he sees one approaching.

Model aircraft flying hot spots


(i) Tai Tong in Yuen Long;

It is also of paramount importance that model aircraft operator KEEP A SAFE DISTANCE between his model and people and property on ground as the model may cause serious injuries or even fatalities and serious damage on impact.

(iii) Tate's Cairn in Sha Tin;

RECKLESSLY OR NEGLIGENTLY CAUSING OR PERMITTING A MODEL AIRCRAFT TO ENDANGER ANY PERSON OR PROPERTY IS LIABLE TO PROSECUTION. Where you cannot fly a) Model aircraft shall not be flown over populated and congested areas. b) Model aircraft shall not be flown over, or close to, any object, installation or facility that would present a risk to safety in the event of damage due to any impact by the model aircraft, or in such a manner that the good order and discipline and control thereof may be or may likely be jeopardized. c) Model aircraft shall not be flown in the vicinity of an airport and main aircraft approach and take-off paths. These areas include: (i) Hong Kong International Airport; (ii) North Lantau coastal area; (iii) coastal areas from Tai Lam Chung to Tsuen Wan and Tsing Yi Island; (iv) coastal areas at both sides of the Victoria Harbour; and (v) Shek Kong area. Altitude of Operations The altitude of operations shall not exceed 300 feet above ground level. Time of Operations The operations of model aircraft shall be conducted during daylight hours only.

The following places are frequently visited by the public for model aircraft flying:

(ii) Nam Sang Wai in Yuen Long;

(iv) Tseung Kwan O in Sai Kung; and (v) Clear Water Bay Peninsula area in Sai Kung.* * The hilltops at Clear Water Bay Peninsula are within the passages of air traffic used by light aircraft and helicopters. The operator of model aircraft should therefore ensure the safe passage of such air traffic, especially in poor weather conditions when pilots are forced to fly much lower than usual. Caution: Safety measures must always be observed even when flying model aircraft in these hot spots. Heavy model aircraft Except with Civil Aviation Department's endorsement, heavy model aircraft weighing more than 7 kg (without its fuel) are not allowed to fly in Hong Kong. Learning to fly One of the best ways to learn to fly is to join a model flying club or to get help from an experienced model aircraft operator. Safety guidelines on flying of model aircraft of some model flying clubs are accessible via the following links: Hong Kong Model Flying Association, HK Model Engineering Club Ltd, HK Radio Control Soaring Society, RC Model Helicopter Club Remember to: EXERCISE GOOD AIRMANSHIP, BE CONSIDERATE, AND KEEP YOUR HOBBY SAFE. A COLLISION CAN KILL

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