Pilot Hand Book.docx

What is a Drone?

A drone, technologically termed an Unmanned Aerial Vehicle (UAV) or part of an Unmanned Aerial System (UAS), consists of a UAV, a ground-based controller, and a communication system. It's a flying robot without a human pilot, remotely controlled or operated autonomously via software-controlled flight plans and onboard sensors. . Drones come in various shapes and sizes, serving a multitude of purposes, including aerial photography, surveillance, delivery services, and agricultural monitoring.

A Brief History of Drones

• 1849: Austrians attacked Venice using unmanned balloons loaded with explosives.

• Battle of Neave Chapelle: The British Military used aerial imagery to capture approximately 15,000 sky view maps of German trench fortifications.

• Abraham Kareem: Known as the father of drones, he created robotic planes that transformed modern warfare, notably the Predator UCAV.

Civil Drone Applications

• Shipping & Delivery: While under development, drone delivery could revolutionize the world by improving delivery times and reducing human labor for items like pizzas, letters, and small parcels.

• Disaster Management: Drones are crucial in disaster management to address post-disaster chaos and mismanagement of resources, providing significant assistance in man-made or natural calamities.

Media

• Drones have greatly impacted the movie industry, enabling shots that were previously impossible. Examples include movies like James Bond’s Skyfall, The Wolf of Wall Street, Harry Potter and the Chamber of Secrets, and TV series like Game of Thrones.

• Drones are increasingly used in journalism due to their ability to access locations reporters cannot, enhancing live broadcasts with aerial footage.

Law Enforcement

• Drones can hover around locations unnoticed, making them useful for surveillance and public safety, monitoring crowds, and detecting criminal activity.

• They provide detailed views of crime scenes and can assess fire outbreaks before human intervention.

• Border patrol officials use drones to monitor criminal activity, particularly drug transport.

• Traffic surveillance with drones is another significant application.

Archeological Surveys & 3D Geographic Mapping

• Drones simplify archeological surveys by providing essential footage and details about sites.

• They enable the study of terrain and preparation of 3D maps in inaccessible regions such as dangerous coastlines and mountain tops.

Wildlife Monitoring

• Drones monitor wildlife, preventing poaching and enabling the study of animal behavior without disturbance, including nighttime monitoring with thermal camera sensors.

• Wildlife sanctuaries and conservation parks use drones to ensure safety.

Rescue Operations

• Drones equipped with thermal sensors locate lost persons, especially at night or in challenging terrains. They can be rapidly deployed and navigate small spaces.

• Drones also deliver food or medical supplies to unreachable locations ahead of rescue teams.

Infrastructure Inspection

• Drones inspect power lines, oil and gas pipelines, wind turbines, bridges, and buildings under construction. Regular aerial monitoring improves infrastructure construction and performance. Small drones capture detailed imagery of construction.

Agriculture

• Drones improve crop yields through regular aerial monitoring, providing in-depth analysis of crop performance using near-infrared sensors to assess crop health. This analysis can be performed at low costs with minimal environmental impact.

Weather Forecasting

• Drones with cameras and sensors collect data for weather forecasts, including studying hurricanes and tornadoes. Their unmanned nature makes them suitable for focusing on detailed weather parameters.

Aerial Views

• Drones equipped with improved technology and heavy camera gear provide aerial views of specific regions with stable and clear images. Live Wi-Fi streaming provides First Person Views (FPV).

• Adding a gimbal stabilizes the camera, and smartphones can control the camera and capture HD video.

Bomb Detection

• Small and effective cameras enable drones to penetrate constricted spaces, making them suitable for bomb detection.

Defense

• Drones conduct regular surveys for national protection, reducing manual labor and providing a wider field of view without disrupting civilian life.

Air Strikes

• Drones are used for air strikes in military operations, having been used to attack militants in tribal areas, controlled by defense personnel.

Regulatory Framework

• Directorate General of Civil Aviation (DGCA): The primary regulatory body in Indian Civil Aviation, dealing with safety issues and regulating air transport services to/from/within India. It enforces civil air regulations, air safety, and airworthiness standards. Headquartered in New Delhi.

• Drone Rules 2021: Dated August 25, 2021.

• The Aircraft Act, 1934: An act to control the manufacturing, possession, use, operation, sale, import, and export of aircraft.

• The Director General or any officer of the DGCA can inspect UAS, manufacturing, storage, maintenance facilities, UAS traffic management facilities, or any related facility for authorization, certification, or licensing under the Aircraft Act, 1934.

• UNMANNED AIRCRAFT SYSTEM (UAS) RULES, 2021: Published on March 12, 2021. These rules apply to UAS registered in India, UAS owned or operated in India, or all UAS in India.

Aerodynamics Fundamentals : Understanding the principles of aerodynamics is crucial for effective operation of any aircraft, including Unmanned Aircraft Systems (UAS), as it governs the behavior of the aircraft in flight, such as lift, drag, thrust, and weight.

• The aerodynamic forces acting on an aircraft involve principles governing aircraft behavior in flight, including aerodynamics, propulsion, and weight distribution.

• The study of air behavior as it interacts with solid objects, particularly the forces acting on a body moving through the air. in drones

Forces

• Thrust: Force produced by the power plant/propeller or rotor, acting opposite to drag, usually parallel to the longitudinal axis.

• Lift: Force opposing weight, produced by the dynamic effect of air moving over the airfoil, acting perpendicular to the flight path through the Centre of lift.

• Weight: Combined load of the aircraft. It acts vertically downward through the aircraft’s Centre of gravity (CG).

• Drag: Rearward force caused by airflow disruption, opposing thrust, acting rearward parallel to the relative wind.

Axis of an Aircraft

• The aircraft axes are three imaginary lines that pass through the CG at 90° angles. These axes serve as imaginary axles.

• Longitudinal Axis: Passes through the CG, parallel to a line from nose to tail.

• Lateral Axis: Passes parallel to a line from wingtip to wingtip.

• Vertical Axis: Passes through the CG at right angles to the other two axes.

• Aircraft rotate about one or more of these axes to change flight attitude or position.

Motions

• Roll: Controlled by ailerons,the aircraft rotates about its longitudinal axis, allowing it to bank left or right during turns.

• Pitch: Controlled by elevators,which adjust the angle of the aircraft's nose up or down, allowing for ascent or descent.

• Yaw: Controlled by the rudder,which allows for directional stability and allows the aircraft to turn left or right.

• Throttle: Controlled by the throttle lever, which adjusts engine power and speed.

Aerodynamics Principles

• Bernoulli's Principle: Air passing over an airfoil travels faster than air underneath, creating lower pressure above and higher pressure below, thus generating lift.

• Aircraft remain airborne due to the forward thrust of wings or airfoils. The thrust moves the wing, generating lift perpendicular to the motion, overcoming gravity.

• Drag represents air resistance against the wing, dependent on the effective area of the wing facing the airflow and airfoil shape.

• Lift and drag magnitudes depend on the angle of attack between the wing’s motion direction and the chord line of the wing.

• NASA's Lift Equation: http://grc.nasa.gov/www/k-12/airplane/lifteq.html

Phases of Flight In Drones

• Takeoff: The drone ascends from the ground to a predetermined altitude, often employing a combination of lift generated by its rotors and thrust to achieve elevation.

• Climb: After takeoff, the drone continues to ascend, adjusting its angle of attack to increase lift and minimize drag.

• Cruise: The drone maintains a steady altitude and speed, optimizing its energy efficiency while navigating to its destination.

• Descent: The drone gradually decreases altitude, often leveraging controlled descents to manage speed and stability.

• Landing: The final phase involves safely returning to the ground, employing a combination of lift and thrust reduction to ensure a smooth touchdown.

Flight Path Legs : Each segment of the flight involves specific actions and adjustments, including altitude changes, speed management, and monitoring of environmental conditions to ensure a successful journey.

• Departure/Upwind Leg: Climbing flight path along the extended runway centerline.

• Crosswind Leg: Short climbing flight path at right angles to the departure end of the runway.

• Downwind Leg: Long level flight path parallel to the landing runway, with early, mid, and late sub-legs.

• Base Leg: Short descending flight path at right angles to the approach end of the runway.

• Final Approach: Descending flight path along the runway centerline from the base leg to the runway.

ATC Procedures and Radio Telephony

• Remote pilots must be fully conversant with ATC procedures and Radio Telephony. This includes understanding standard phraseology, knowing how to request clearance, and maintaining effective communication with air traffic controllers throughout the flight.

• Additionally, remote pilots should familiarize themselves with the different types of clearances required for various flight operations, such as takeoff, landing, and in-flight navigation.

Required Knowledge

1. Basics of Radio Telephony (RT) techniques and radio frequencies.

2. Flight planning and ATC procedures.

3. Regulations for the area of operations.

4. Airspace structure and restrictions (No drone zones).

5. Basic Aviation Meteorology.

Standard Radio Terminology and RT Phraseology

Pilots and air traffic controllers use standardized radiotelephony phrases approved by ICAO:

• ACKNOWLEDGE: Confirm receipt and understanding.

• ADVISE: Inform on/of/about.

• AFFIRM: Yes.

• AIRBORNE: Flight started after take-off.

• APPROVED: Permission granted.

• BREAK: Indicates separation between message portions.

• BREAK-BREAK: Separates messages for different addressees in busy environments.

• CANCEL: Annul previous clearance.

• CAUTION: Beware of following conditions.

• CHECK: Examine a system or procedure.

• CLEARED: Authorized to proceed under specified conditions.

• CLIMB: Climb to maintain (level out).

• COMPLY: Act as requested.

• CONFIRM: Request verification.

• CONTACT: Establish communications with.

• CORRECT: True or accurate.

• CORRECTION: Error in transmission; correct version follows.

• CROSS: Fly/taxi across.

• DEPART: Leave.

• DEPARTURE: Take-off, departing.

• DESCEND: Descend to maintain (level out).

• DISREGARD: Ignore.

• ESTIMATE: Calculate/approximate.

• EXPEDITE: Speed up.

• HOLD: Keep in place.

• HOLD SHORT: Keep away of.

• HOW DO YOU READ: What is the readability of my transmission?

• IMMEDIATELY: Without delay.

• I SAY AGAIN: Repeat for clarity.

• LEAVE: Depart, abandon.

• LOOK OUT (FOR): View over, survey inspection.

• MAINTAIN: Continue in accordance with conditions.

• MONITOR: Listen out on (frequency).

• NEGATIVE: No/Permission denied/Incorrect/Not capable.

• OUT: Transmission ended, no response expected (rarely used in VHF).

• OVER: Transmission ended, response expected (rarely used in VHF).

• READ: Hear and understand.

• READ BACK: Repeat message exactly as received.

• SAY AGAIN: Repeat all or part of transmission.

• SLOW DOWN: Reduce speed.

• STANDBY: Wait, I will call you.

• WILCO: I understand and will comply.

Sample Communication for Drone Operations in Controlled Airspace

• DRONE OPERATOR to ATC: "Good morning/afternoon/evening tower! Unmanned (call sign/UIN number) requesting clearance to commence Flight Operations as filed."

• ATC to DRONE OPERATOR: "Good morning/afternoon/evening Unmanned (Call Sign). Clearance: cleared ……. Call/Report for start-up."

• DRONE OPERATOR to ATC: "Unmanned (Call sign), clearance copied (read-back clearance). Will call/report for start-up."

• DRONE OPERATOR to ATC: "Unmanned (Call sign) ready for departure, position [ ]."

• ATC to DRONE OPERATOR: "Unmanned (call sign), cleared to commence operations, takeoff from present position, call [reaching reporting point/ established/ at specific time with a position report/ inbound/ landed/ operations complete]."

• DRONE OPERATOR to ATC: "Tower, Unmanned(Call sign) clear takeoff from present position, commencing operations at [Time in Zulu] in Sector ABC, X nautical miles, Ht. AGL. Shall maintain listening watch on frequency 123.45 and secondary communications via( operator’s phone number). Will call complete."

• DRONE OPERATOR to ATC: "Tower, unmanned (call sign), Time [Zulu] [ established/ position report/ inbound/]."

• DRONE OPERATOR to ATC: "[landed/ operations complete] Request Closing flight plan."

• ATC to DRONE OPERATOR: "Unmanned (call sign), flight plan closed/terminated. Good Day!"

Phonetic Alphabet

• A- ALFA, B- BRAVO, C- CHARLIE, D- DELTA, E- ECO, F- FOXTROT, G- GOLF, H- HOTEL, I- INDIA, J- JULIET, K- KILO, L- LIMA, M- MIKE, N- NOVEMBER, O- OSCAR, P- PAPA, Q- QUEBEC, R- ROMEO, S- SIERRA, T- TANGO, U- UNIFORM, V- VICTOR, W- WHISKEY, X- XRAY, Y- YANKEE, Z- ZULU.

• 1 - WUN, 2 - TOO, 3 - TREE, 4 - FOW-ER, 5 – FIFE, 6 - SIX, 7 – SEV-EN, 8 - AIT, 9 - NIN –ER, 0 - ZEE-RO.

Pre-Flight & Take-Off Communication Protocol

• RPA to ATC (Station): "Unmanned (XYZ) on pad (Number H-1/2/3) at (GCS Location) (Lat: Long:) requesting start-up clearance with information (MET) for flight plan as filed. (ADC: FIC)"

• ATC to RPA: "Unmanned (XYZ) start-up approved from pad (Number) at (GCS Location) report ready for departure."

• RPA to ATC: "Unmanned (XYZ) ready for departure."

• ATC to RPA: "Unmanned (XYZ) clear to operate within geo fence boundary (A), climb to (FT) AGL report reaching (Designated point) (FT) AGL."

• RPA to ATC: "Unmanned (XYZ) clear to (Read back instructions) engaging rotors."

• ATC to RPA: "Unmanned (XYZ) clear take-off."

• RPA to ATC: "Unmanned (XYZ) Airborne, proceeding to (Designated point) (FT) AGL."

• ATC to RPA: "Unmanned (XYZ) copied, call reaching (Designated point)."

• RPA to ATC: "Unmanned (XYZ) reporting (Position and height). Estimated duration (HH:MM) will call (Transit/inbound)"

• RPA to ATC: "Unmanned (XYZ) Copied (Read back Instruction)"

• ATC to RPA: "Copied Unmanned (XYZ)"

• RPA to ATC: "Unmanned (XYZ) request transit to (New altitude/ position)"

• ATC to RPA: "Unmanned (XYZ) (Negative hold- will inform when clear) or (Cleared transit to requested point) (Hold altitude or descent/climb altitude or report transiting to altitude)"

• RPA to ATC: "Unmanned (XYZ)Roger, copied will (Read back instructions)"

• RPA to ATC: "Unmanned (XYZ) at point(B) requesting (Climb/descent/transit/experiment)"

• ATC to RPA: "(Cleared to climb/descent/transit/experiment) or (Negative hold/ Standby for clearance.)"

• RPA to ATC: "Unmanned (XYZ) Copied (Read back Instruction)"
  RPA to ATC: Unmanned (XYZ) at (Position & Altitude) requesting inbound for landing.
  ATC to RPA: Unmanned (XYZ) (Climb/descent/transit) to altitude (FT), report reaching (Position)
  RPA to ATC: Unmanned (XYZ) at (Position) requesting landing clearance.
  ATC to RPA: Unmanned (XYZ) report positive visual contact overhead pad (Number H-1/2/3)
  RPA to ATC: Unmanned (XYZ) visual, overhead pad (Number H-1/2/3)
  ATC to RPA: Unmanned (XYZ) copied, contact GCS Location UTM/GCS for landing clearance.
  RPA to ATC: Unmanned (XYZ) GCS Location UTM/GCS visual, overhead pad (Number H-1/2/3) request landing clearance.
  GCS Location: UTM/GCS: Unmanned (XYZ) Winds (W/V) Clear to land pad (Number H-1/2/3) call rotors disengaged and RPAS shutdown.
  RPA to ATC: Unmanned (XYZ) Copied, cleared to land pad (Number H-1/2/3)
  RPA to ATC: Unmanned (XYZ) on ground at pad (Number H-1/2/3) rotors disengaged, Shutting down RPAS
  GCS Location UTM/GCS: Unmanned (XYZ) Contact ATC (Station) for flight plan termination.
  RPA to ATC: Unmanned (XYZ) Copied shall contact ATC (Station) for flight plan closure, thank you for your assistance, signing off Unmanned (XYZ) over and out
  RPA to ATC: ATC (Station) Unmanned (XYZ) on pad (Number H-1/2/3) Rotors disengaged. RPAS Shutdown at time (Zulu) Thanking for your assistance. Good day.
  ATC to RPA: Unmanned (XYZ) details copied; Flight plan closed. Good day.

• RPA to ATC: "Situation report"

• If RPA is in IFR WEATHER CONDITION or ABOVE MAXIMUM MANEUVERINGS ENVELOPE, indicate:

  • (WEAK LINK, LOSS OF TELEMETRY, LOSS OF CAMERA, BATTERY FAILURE, ENGINE PROBLEM) or

  • (LOSS OFC1 [COMMAND]/ C2[CONTROL] / C3 [COMMUNICATION] LINK)

  • Last noted position (Attitude, altitude, airspeed, heading).

  • Attempting re-establishing link.
    *Requesting control descent of RPAS to land/ divert to alternate (Position).

• ATC to RPA: "acknowledged, report status every 5 minutes until link re-established or confirmation of RAS Status."
  Ensure clearances are obtained from regulators: [MOCA] [DGCA] [AAI] [IAF] [POLICE] [MHA] [RPAS INSURANCE] [Flight plan filed] [NOTAM] [FIC¬ & ADC] [MET Information] [ATC Clearance]

• Emergency contact details [ATC] [DGCA] [Hospital] [Police station] [Fire station] [Organization Chart.]
  Check if carrying: appropriate clothing and footwear, Covid Protection, High Visibility Jackets & Headgear, ID Lanyard & Whistle, Backpack & water bottle, Notebook & Pen, Operations checklist.

• Pre-ops briefing & Pilot briefing [Experiment/ flight operations for the day, duties & responsibilities, safety and security briefing.
  GCS setup check
  UTM Setup check
  ATC-UTM-GCS Communication established
  Emergency alternate communication tested
  Equipment:
  [Electrical Backup] [Safety Equipment] [Fire Extinguisher] [First Aid Kit]
  [Transport and logistics vehicle] [Water supply & Food]
  ACTIVE AIRSIDE OPERATIONS AREA CLEARED>>>SECURITY CORDON BAND>>>WORKSITE CONES>>>CAUTION SIGNS
  [Anemometer] [Windsock] [Landing pad] [Megaphone] [High beam torch] [Binoculars] [Tent] [Table] [Chairs] [Carry cases] [Waste bin] [File Brief] [Sanitizer]
  RPAS carrying permit letter.

Advantages and Disadvantages of Fixed Wing UAS

Advantages

• Simple Structure

• Comparatively Simple Maintenance / Repair Process

• Aerodynamic Stability

• Better Energy Efficiency

• Average flight time: up to 5+ hours with gas engine

• Flies at high altitudes

• Higher weight capacity

Disadvantages

• Requires runway/launcher for takeoff and landing.

• Requires constant forward motion to generate lift; cannot hover.

• Can be expensive.

Typical Uses

• Generally used for commercial purposes such as aerial mapping, inspection, agriculture, construction, security, and surveillance.

Single Rotor Drones

• Strong, similar to helicopters with one large rotor and a smaller tail rotor for direction and stability.

Advantages

• Vertical hovering

• Built strong and durable

• Long-lasting endurance with gas power

• Heavy load capability

Disadvantages

• Harder to fly than multi-rotor drones

• Expensive

• Higher complexity

• Dangerous because of heavy spinning blades

Typical Uses

• Research, Arial LIDAR laser scan, Surveying.

t or cold something is and it is measured in degrees Celsius/Fahrenheit (°C/°F). Temperature has a direct relation to density which affects aircraft performance, temperature has an effect on weather phenomenon and also some aircraft components have their own temperature limitations.

Multi Rotor Drones

• Popular for aerial photography, filmmaking, and surveillance; used by professionals and hobbyists; small size and ready-to-fly capabilities.

• Easiest to manufacture and cheapest drones.

• Carry several rotors: tri-copters (3 rotors), quadcopters (4 rotors), hexacopter (6 rotors), octocopter (8 rotors).

Advantages

• Very easy to control and maneuver

• Ability to hover

• Vertical takeoff and landing

Disadvantages

• Limited endurance (15 to 20 minutes)

• Small payload capabilities

• Most energy spent on fighting gravity and stabilizing in the air

Typical Uses

• Aerial Photography and video aerial inspection, leisure, agriculture, construction, and security.

Aircraft Controls

• Four main controls: Ailerons (roll), Rudder (yaw), Elevators (pitch), and Throttle (speed).

Aircraft Maneuvers

• Roll rotates wings around the fuselage; Pitch climbs and descends; Yaw turns the nose; Thrust controls speed.

RPAS Components

• UAV, Ground Control Station (GCS), Mission planning equipment “ Communication data link, Flight parameters

Controls - Action and RC Transmitter Position with Copters responding Behavior

• Pitch forward - left stick; up position goes forward - pitch value increases,

• Pitch backward - left stick; down position goes backward - pitch value decreases,

• Roll right - left stick; right position goes right - roll value increases,

• Roll left - left stick; left position goes left - roll value decreases,

• Yaw right - right stick; right position heading turns to right yaw value increases,

• Yaw left - right stick; left position heading turns to left yaw value deceases

• Throttle up - right stick; up position goes up throttle value increases,

• Throttle down - right stick; down position goes down throttle value decreases,

Transmitter Components

1. CH5 - For arm/disarm switch

2. Power switch - To turn on the transmitter

3. Switches - To reverse the RC values and to set the transmitter mode

4. LED indicator - If light is blinking, replace the A4 battery.

5. Roll movement- For UAV roll control

6. Pitch movement - For UAV pitch control

7. Throttle movement - For UAV throttle control

8. Yaw movement - For UAV yaw control

9. Roll Trim - For trimming roll by small amount

10. Pitch Trim - For trimming pitch by small amount

11. Throttle Trim - For trimming throttle by small amount

12. Yaw Trim - For trimming yaw by small amount

Direction of Moving Motors / Motor Orientation with Force acting on the Drone

Axis and Motion - Hybrid VTOL UAVs

• Combine multi-rotor and fixed-wing benefits transition between modes in flight.

• Versatile for commercial/military uses.

• Vertical take-off and landing (VTOL): operate from almost any location

• Fixed-wing design: provides greater endurance for longer distances, and faster speeds, allowing operators to fly longer

VTOL UAV Types

• Tail sitter VTOL, Standard VTOL, Tiltrotor VTOL

VTOL UAV Benefits

• Vertical takeoff and landing: Even pilots can take off and land. any location

• Fast and efficient fixed wing flight: Faster, missions, heavier payloads.

• Hovering: Steady platform for photography, structure scans etc.

VTOL FLIGHT MODES
PLANE FLIGHT MODES MULTIROTOR FLIGHT MODES
FBWA ALT HOLD
FBWB LOITER
CRUISE RTL
CIRCLE RTL
LOITER

Applications

• Mapping & Land Surveying: can rapidly deploy in remote areas, and provide real-time geospatial data.

• Mining: deployed safely and efficiently to mining areas and allow for increased productivity.

• Surveillance & Security: can provide real-time intelligence to decision-makers, allowing better pre-planning, greater control and more efficient resolution of emergency situations without putting human operators in harm’s way

Essential Components Remotes

A radio control system consists of a transmitter held by the operator and a receiver inside the UAV. The transmitter reads stick inputs and sends them to the receiver in real time. The receiver passes this information to the UAV’s flight controller.
A radio will have at least four channels for each direction on the sticks plus extra ones for any switches.

Batteries and Charging

Lithium Polymer batteries (LiPo), are popular for long run times and high power; they require specialized charging. They charge using Constant Current / Constant Voltage. The charger keeps the current constant until the battery reaches peak voltage (4.2v per cell) and then maintains that voltage while reducing the current.

Propellers

When rotated, a propeller transforms rotational power into linear thrust by acting upon a working fluid, such air.

Flight Controller

A flight controller is a small circuit board. It directs the RPM of each motor via an Electronic Speed Controller or a control surface via a Servo in response to input. The majority of flight controllers employ sensors to supplement their calculations.

Electornic Speed Controller

An electronic speed control (ESC) is an electronic circuit that controls and regulates the speed of an electric motor. It may also provide reversing of the motor and dynamic braking. Miniature electronic speed controls are used in electrically powered radio control vehicles like RPAS.

Brushed DC / Brushless DC (BLDC) Motors

A brushless DC electric motor are permanent magnet synchronous motors (PMSM) powered by direct current via a switching power supply

What is weather?

Weather is the state of the atmosphere at a particular place and time as regards heat, cloudiness, dryness, sunshine, wind, rain, etc.

International Standard Atmosphere

ICAO STANDARD ATMOSPHERE Height Km & ft. Temperature Pressure hPa Lapse Rate
0 km MSL 15.0 1013.25 - 1.98(troposphere)

Pressure

Atmospheric pressure, or air pressure, is the force exerted on a surface by the air above it as gravity pulls it to Earth measured with a barometer and is expressed in Millibars (mb), hecto- Pascal (hPa) or inches of mercury. Instruments use air pressure measurement to get their readings and have a direct influence on aircraft performance.

Temperature

Temperature is how

Wind

Moving air is called wind. It is caused by the uneven heating of the Earth’s surface by the sun and the Earth's own rotation. Winds range from light breezes to natural hazards such as hurricanes and tornadoes. It is measured in Knots. Winds affect aircraft performance and it also has an effect successfully navigating to the desired destination.

Clouds

• A cloud is an aggregate of visible form of water droplets or ice particles, produced by condensation and deposition of water vapor in the atmosphere

• There are 10 major genres of clouds classified on the basis of Form and Height

• Form they are layered, Cumuliform or developing, Cirri form or high cloud, Mid‐level clouds are classified as Alto whilst moisture bearing clouds are called Nimbo.

• There are ten main types of clouds: Altocumulus, Altostratus, Cirrocumulus, Cirrostratus Cirrus, Cumulonimbus, Cumulus, Nimbostratus Stratocumulus Stratus

We can identify these different kinds of clouds in three main ways

• Shape

• Height in the sky

• Whether it is accompanied by other weather conditions

Three categories of Clouds

1 ) Low clouds 2 ) Medium clouds 3 ) High clouds

Low Clouds

Stratus:

• Flat layer of clouds, gray or white in color

• Create a gloomy weather.
  Stratocumulus:

• Similar to cumulus clouds, but flatter, thicker, and darker. Fluffy white shape.

• Appear before or after a front/when there is weak convection in the atmosphere
  Nimbostratus:

• Large thick layer of gray clouds

• Bring steady rain or snow.
  Cumulus:

• Fluffy clouds that are white with a gray base.

• Often described as looking similar to cauliflower and signify a sunny day.
  Cumulonimbus:

• Dense and towering gray clouds

• Associated with thunderstorms.

Medium Clouds

Altostratus:

• Thick and flat white/ light gray clouds.
  establishes a blanket across the sky at mid-level. no shades of blue.

• Usually indicate warmer weather is approaching; can cause light precipitation form a white or gray layer that blankets the sky at mid-level. There are usually no patches of blue sky when these clouds appear, but the sun is often visible as a dimly lit disk behind the clouds (although no shadows appear on the ground).
  Altocumulus:

• Round white/ gray patched in sky, that has often been described like wool or fish scales.

High Clouds

Cirrus:

• Wispy clouds located high in the atmosphere are likely cirrus clouds.
  establishes a white wispy shape

• May mean a warm front is approaching.
  Cirrostratus:

• Transparent wispy sheet of cloud can have a halo or ring of lights surrounding the sun or moon.
  Cirrocumulus:

• smaller than most other types , made in sections

• Sunny and cold

• The Towering Cumulus Stage,The Mature Cumulus Stage

Thunderstorms

• A violent short-lived weather disturbance that is almost always associated with lightning, thunder, dense clouds, heavy rain or hail, and strong gusty winds.

• Thunderstorms arise when layers of warm, moist air rise in a large, swift updraft to cooler regions of the atmosphere.

METAR (METEROLOGICAL TERMINAL AVIATION ROUTINE WEATHER REPORT)

• METAR is a format for reporting weather information used by aircraft pilots and meteorologists help in weather forecasting.

Elements of a METAR

• Station for which the weather is being reported

• Date and time of issue

• Wind Direction and Speed

• Visibility

• Precipitation/Visible moisture

• Cloud cover and Altitude

• Temperature and Dew point

• Pressure/Altimeter setting

• Trend

Recommendations

*Carry handheld devices displaying localized pressure altitude, temperature, etc., for better local flying conditions to affect aircraft performance.

Decode Metar For practice Examples

1) VIDP 190630Z 21005KT 5000 HZ SCT035 FEW040CB BKN100 36/24 Q1001NOSIG
2) VABB 190630Z 24010G20KT 2500 HZ FEW012 SCT018 FEW030CB BKN090 29/27 Q1006 TEMPO 1500 SHRA=
3) VOMM 190630Z 30008KT 7000 FEW020 SCT100 33/26 Q1006 NOSIG=
4) VOHS 190630Z 24011G21KT 6000 SCT015 SCT025 28/21 Q1010 NOSIG=
5) VEGT 190630Z 31006KT 5000 HZ SCT018 FEW025CB BKN100 33/27 Q1001 NOSIG=
6) VILK 190630Z 07005KT 5000 HZ SCT020 SCT025 36/28 Q1000 NOSIG=
7) VECC 190630Z 25006KT 3500 HZ SCT018 SCT025 32/27 Q1001 NOSIG=

Maintenance and Inspection Ensure

a) sufficient batteries are carried and fully charged to complete the mission.
b) Spare propellers.
c) Any tools that maybe required to carry out minor fixes.

When carrying out an inspection

• Ensure the drone is powered down and batteries disconnected.

• Inspect the drone to ensure there is no structural damage.

• Inspect propellers to ensure no cracks or bends and properly fixed and freely spinning.

• Inspect the camera and gimbal to ensure no dust/dirt/damage.

• Inspect the battery for any

1. Learning Objectives

• Understand the definitions of hazard and risk in UAV operations.

• Learn the phases of UAS safety risk assessment and management.

• Identify potential UAV operational hazards and emergencies.

• Apply appropriate mitigation strategies and emergency procedures.

• Build a safety-first mindset through documentation and continuous monitoring.

2. What is a Hazard?

• Definition: A source, situation, or act with the potential to cause harm, injury, or damage.

• Example: A lion out of its cage (dangerous situation).

• Drone Context: Flying near power lines, strong wind zones, or dense populations.

3. What is a Risk?

• Definition: The combination of the likelihood of a hazardous event and its potential severity.

• Formula:
  Hazard → Exposure/Action → Risk
  Risk = Probability × Severity

• Example: Flying a drone in strong winds → higher probability of crash → high risk.

4. Risk Management Approach

• Risk Matrix: Develop your own criteria to decide "Go" or "No-Go" for flights.

• Important: There’s no fixed score, but your matrix should guide acceptable risk levels.

5. Risk Assessment Phases

Part I – Hazard Identification

• Identify events like near-misses, IMU failures, crashes, loss of control, etc.

Part II – Risk Assessment

• Assess the severity (harm/damage) and probability (likelihood) for each hazard.

Part III – Risk Mitigation

• Define and apply control measures based on risk levels (Unacceptable, Tolerable, Acceptable).

Part IV – Documentation

• Maintain records of risk assessments, hazards, mitigation plans, and flight logs.

6. Common UAV Hazards

1. Loss of altitude

2. Loss of control

3. Loss of transmission

4. Mid-air collisions (manned/unmanned)

5. GPS/navigation failures

6. Severe weather

7. Corrosion

8. Pilot unfamiliarity with area

9. Rotor failures

10. Take-off/landing errors

7. Safety Risk Severity Levels (Example Table)

8. UAV Safety Risk Acceptance Matrix

9. Emergency Procedures

Types of Emergencies

• Fire

• Medical

• Environmental

• Human (e.g., pilot disorientation)

• Technical (hardware/software)

Common Drone Emergencies & Remedies

10. Threat and Error Management (TEM) in Drone Ops

11. Summary (Key Points)

• Hazards become risks when exposed to action.

• Risk = Probability × Severity.

• Use a structured risk assessment process (Identification, Assessment, Mitigation, Documentation).

• Prepare for emergencies using RTL functions and manual override procedures.

• Maintain a documented safety culture with regular monitoring.

12. Examples and Case Studies

• Case 1: Drone crash due to uncalibrated compass — resulted in flyaway.

• Case 2: Rotor damage mid-flight — pilot activated manual control and performed safe landing.

• Case 3: Battery emergency handled by RTL function, drone landed 30 meters from take-off site.

• Case 4: Human emergency – pilot fainted; co-pilot took over flight controls.

13. References

• ICAO Safety Management Manual

• DGCA CAR 1 Series X Part I

• FAA UAS Risk Assessment Guidelines

• ARPAS-UK Drone Risk Matrix

• OEM Drone Manuals

14. Q&A Section (5–7 Questions)

Q1. What is the difference between a hazard and a risk?
A hazard is a potential source of harm; a risk is the possibility of that harm occurring due to exposure.

Q2. What are the four phases of UAV risk assessment?
Hazard Identification, Risk Assessment, Risk Mitigation, and Documentation.

Q3. What emergency action is triggered during a communication failure?
Return to Launch (RTL) is automatically activated.

Q4. Name two common technical emergencies in UAV flights.
IMU failure and motor/propeller damage.

Q5. How can risk be quantified in drone operations?
By using a matrix that measures both probability and severity.

Q6. What is the recommended action for a geofence breach?
Auto RTL (Return To Launch).

Q7. Why is documentation important in safety risk assessment?
It supports continuous improvement and acts as evidence for compliance and training.