# Flight Training In Close Proximity of Structures, Vegetation, and Power

Lines

• Pilot and observer procedures

• Anticipated aircraft behavior, updrafts, wind shear mechanical turbulence



## • Anticipated autopilot behavior, GPS poor flight, Semi

- Auto, manual

1 © Alfred A. Gates, 2014

# Pilot and Observer Procedures

• The observer has equal rolls in producing a safe and beneficial flight around structures

• When the plot maneuvers a fixed wing aircraft to a safe distance away from the target he will stop and hold position by switch to semi

- auto or auto and circle a point.

• The pilot should not move from his view point once the observer is providing guidance. Also the pilot should only be looking at the aircraft and if he must look at the controller he should move the controller to his line of sight.

• In close proximity of structures, vegetation and lines, the observer will have a better understanding of the position of the aircraft using the video monitor.

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# Pilot and Observer Procedures

• During any stage of the 

## flight

• The pilot will put the transmitter in the field of 

## view to check the flight status, GPS signal strength, battery strength.

34  Pilot: Eyes always on the aircraft  Observer: Advises pilot during every position change

• Operates all camera functions

• Moves around to vide aircraft from different angles

• Uses video feed to advise pilot

# Winds/ Weather

• On calm days the winds were stronger than anticipated requiring the pilot to manually fly the fixed wing aircraft in close proximity to the structures and power lines.

• Biggest limiting factor is weather. Winds greater than 15KTS coupled with other factors that create wind require over riding the GPS mode.

• Can not fly in rain or snow showers.

• A highly experienced pilot is required.

• The observer has a higher work load than anticipated.

2015 AHS Specialist’ Meeting on Unmanned Rotorcraft and Network

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Operations Program 5

# Navigation

• It is safer to navigate around wires in Autonomous position hold mode provided the autopilot is capable of maintaining position in the winds. This allows the pilot time to slowly maneuver the aircraft into position. The observer is advising the pilot in close proximity of lines and structures.

• The pilot needs to be ready to switch modes if the aircraft is blown out of position or if the GPS signal becomes weak.

• The maximum pitch and roll angles are decreased in GPS mode when compared with the stabilize and altitude flight modes.

2015 AHS Specialist’ Meeting on Unmanned Rotorcraft and Network

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Operations Program 6Or no wind

This will occur around tree canopies Shear Zone : This will cause an aircraft to move in pitch and roll to maintain attitude control. Wind T op Zone: the aircraft can be blown out of view. FAA Pilots Handbook

2015 AHS Specialist’ Meeting on Unmanned Rotorcraft and Network

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Operations Program 7Still air

Wind Aircraft can be blown out of view Wind shear event

2015 AHS Specialist’ Meeting on Unmanned Rotorcraft and Network

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Operations Program 8Anticipating

• Flight in turbulence (aircraft will move around more)

• Aircraft will be blown in one direction. Pilot is ready to switch modes Wind shear Video: Wind at top of structure

Aircraft was being blown out of view Above tree canopy. Pilot had seconds to switch modes

2015 AHS Specialist’ Meeting on Unmanned Rotorcraft and Network

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Operations Program 9Terrain turbulence

Mechanical Turbulence

2015 AHS Specialist’ Meeting on Unmanned Rotorcraft and Network

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Operations Program 10 Convective Currents

## Fixed Wing UAS Flight Modes Commonly Uses For Structural Inspection

• Manual: Pilot keeps the aircraft level. Does not hold 

### position or altitude (Pilot has the most control authority)

• Semi
- Auto: keeps the aircraft level and at the current 

### altitude if the sticks are released. Does not hold position (Change and altitude is limited by the maximum/ minimum throttle setting programmed)



### • Autonomous: Fly's a preprogrammed pattern. Depends on a good GPS signal.

2015 AHS Specialist’ Meeting on Unmanned Rotorcraft and Network

- Centric

Operations Program 11

## Anticipated autopilot behavior, GPS poor flight, semi
- autonomous, manual

• The pilot must anticipate that the GPS signal 

## strength will decrease. (Be ready to switch modes)

• The pilot must anticipate wind shear, updrafts, 

## wind gust and wind changes. (Be ready to switch modes)

• The pilot must anticipate what the sUAS will do in the event of wind shear, updrafts, wind gust and wind changes

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# Updrafts

• Updraft: Aircraft will climb. Throttle min 

## position will not be low enough to maintain altitude.

• Pilot response:



## • Let the aircraft climb and wait and see it the updraft decays.

• Switch to manual mode if the aircraft 

## continues to climb. Manual mode provides more altitude and atitude control authority

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# Wind Shear

• Wind Shear : Aircraft will pitch and roll and possibly move away from the pattern flight.



## • Pilot response :

• If a structure is close switch to Semi

- Auto mode or manual. If there is no structure close 

## by. Let the aircraft move around and fly the aircraft through the wind shear zone.

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# Wind Gust, Wind Increase

• Wind Shear: Aircraft will blown in one direction.

• Pilot response:



## • If structure is close or if the aircraft is being blown out of view switch to manual mode.

• If there is no structure close by. Let the aircraft 

## move around and see if the wind gust will died down

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# GPS Signal Strength Reduction or

Signal Loss

• When the GPS signal becomes weak. The 

## aircraft will chase a unknown GPS position at the maximum pitch and roll positions. The aircraft will maintain altitude.



## • The pilot must immediately switch modes to a none GPS mode, Semi

- Auto or Manual.

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