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Airframe

When describing the airframe, we first set out the general configuration and summarize the manufacturing methods used (and as already described in earlier parts of this book). We then step through each major part of the airframe with a simple description, photographs, exploded views, cut-away drawings, and any particular notes on aspects that may not be obvious. For one of our large aircraft, this would include sections on the following:

  • 1. Fuselage. Broken down into subsections such as nacelles, main fuselage, integral fuel tank, and so on;
  • 2. Wings. Showing attachment points and the size and location of control surfaces;
  • 3. Tail. Showing attachment points and control surfaces;

Table 19.3 Typical small UAS operations manual template part Bi.

Section

Subject

Comment

Part B

Operating procedures

1

Flight planning/preparation

1.1

Determination of the intended tasks and feasibility

1.2

Operating site location and assessment

(a) the type of airspace and specific provisions (e.g., Controlled Airspace) (b) other aircraft operations (local aerodromes or operating sites) (c) hazards associated with industrial sites or such activities as live firing, gas venting, high-intensity radio transmissions, and so on (d) local byelaws (e) obstructions (wires, masts, buildings, etc.) (f) extraordinary restrictions such as segregated airspace around prisons, nuclear establishments, and so on (suitable permission may be needed) (g) habitation and recreational activities (h) public access (i) permission from landowner (j) likely operating site and alternative sites (k) weather conditions for the planned event using available information from aeronautical charts, the UK Aeronautical Information Service (www .ais.org.uk), digital imagery (Google Earth/Maps, etc.), Ordnance Survey maps, and so on

1.3

Risk management

Identification of the hazards, risk assessment, mitigating procedures

1.4

Communications

Contact numbers for other local aircraft operations

1.5

Pre-notification

If the flight is to be performed within an Aerodrome Traffic Zone, or near to any aerodrome or aircraft operating site, then their contact details should be obtained and notification of the intended operation should be provided prior to takeoff. It may be necessary to inform the local police of the intended operation to avoid interruption or concerns from the public

1.6

Site permission

Reference to document confirming land owners permission

1.7

Weather

Methods of obtaining weather forecasts. Consideration of UAS limitations

1.8

Preparation and serviceability of equipment and UAS

Pre-use checks and maintenance

  • 4. Undercarriage. Illustrating attachment strong points and any suspension and steering components;
  • 5. Engines. Including details such as those shown in Table 19.6;
  • 6. Payload. Often describing a separate pod or bay on the aircraft and indicating the variations in payload that can be accommodated and how such items are fixed.

Table 19.4 Typical small UAS operations manual template parts Bii, C, and D.

Section Subject Comment

Part B

Operating procedures

2

On-site procedures and Preflight checks

2.1

Site survey

Visual check of operating area and identification of hazards

2.2

Selection of operating area and alternate

Size, shape, surrounds, surface, slope. Landing zone for an automatic “home” return should be identified and kept clear

2.3

Crew briefing

To cover the task, responsibilities, duties, emergencies, and so on

2.4

Cordon procedure

Adherence of separation criteria

2.5

Communications

Local and with adjacent air operations if appropriate

2.6

Weather checks

Limitations and operating considerations

2.7

Refueling

Or changing/charging of batteries

2.8

Loading of equipment

Security

2.9

Preparation and correct assembly of the UAS

In accordance with the manufacturers instructions

2.10

Pre-flight checks on UAS and equipment

May be covered in other technical manuals

3

Flight procedures

These procedures may be contained in the “operators manual” or equivalent but should cover all necessary matters including safety

3.1

Start

3.2

Takeoff

3.3

In flight

3.4

Landing

3.5

Shutdown

4

Emergency procedures

4.1

Appropriate to the UAS and control system

Should consider all those events that might cause the flight of the UAS to fail or be terminated

4.2

Fire

Risk and preventative measures should be considered relevant to the type of UAS power sources and fuel

4.3

Accidents

Considerations, responses, and so on

Part C

Training

1

Details of the operator training programme

Training and checking requirements for pilots and support crew as determined by the operator to cover initial, refresher, and conversion syllabi

Part D

Appendices

1

Copy of Authority Permission

This will provide immediate reference to the conditions under which the operations are to be conducted when applicable

2

Other documents

As considered necessary

Table 19.5 Typical summary airframe description.

Item

Characteristic

Units

Length

2.18

m

Wing span

3.92

m

Wing area

1.46

2

m2

Aspect ratio

10.5

Empty weight

23.7

kg

Maximum fuel capacity

8.4

l

Maximum fuel mass

6

kg

Maximum endurance (estimated)

5

h

Maximum payload mass

5

kg

Powerplant

2x OS GF40 with generator

Table 19.6 Typical engine characteristics.

Item

Characteristic

Type

Four stroke

Power

3.75 hp

Displacement

40 cc

Bore

40 mm

Stroke

31.8 mm

Cylinders

1

System weight

1.2 kg

Engine-only weight

1.17 kg

Prop shaft thread

5/16 UNF

Propeller

18x 8 to 20x 10 (two blade)

RPM range

1800-9000 rpm

Fuel

1:50 Mix synthetic oil to unleaded petrol

Carb. type

Walbro WT1070

 
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