The purpose of this article is to give an overview of small aerodrome operations, the typical safety issues and to provide advice on the prevention of runway incursions by visitors, personnel, vehicle drivers and aerodrome managers/owners.
The definition of “small aerodrome” varies from country to country. While there is no strict rule under which any given aerodrome is categorised as being "small", the following features are typical:
- Runway length is 1000m or less;
- The aerodrome serves mostly light aircraft (MTOW of 7000kg or less);
- Number of movements is relatively small
- Limited provision of service (ATC, MET, etc.)
- Most traffic flies under VFR
Typical use of small aerodromes
Small aerodromes are commonly used for general aviation purposes, such as:
- Pilot training
- Parachute jumping
- Leisure flights/sightseeing
- Limited scheduled or non-scheduled passenger services, e.g. commuter aircraft, air taxi, etc.
- Agricultural aviation
Small aerodrome advantages
- Fewer formalities – since most of these aerodromes are domestic, some features such as security checks, customs, etc. are either absent or simplified.
- Less time-consuming – the time between the arrival at the aerodrome and the take-off is usually much less at small aerodromes due to the few formalities and low air traffic levels.
- Cheaper - services such as vehicle and aircraft parking are usually much cheaper as compared to large aerodromes.
- Simple layout - most small aerodromes only have one runway and a few taxiways. This makes it easier for trainees and novice pilots to use the aerodrome.
- Low traffic levels make such aerodromes convenient for pilot training, especially PPL training
Issues related to small aerodromes
- Financing – most of the small aerodromes do not produce sufficient revenue to be able to afford services such as air traffic control, a MET office, rescue and fire fighting services, medical staff, etc nor are they likely to provide ATIS or precision approach capability such as an ILS. Insufficient funds can also lead to safety and security issues.
- Security – most small aerodromes only offer the most basic means of security (if any), such as perimeter fencing.
- Runway incursions – this is one of the main issues, related to small aerodromes. Some of the contributing factors are:
- Higher percentage of non-professional pilots (compared to e.g. large international aerodromes)
- Easy passenger access to the apron (and from there to the maneuvering area, and runway).
- Limited or lack of air traffic services.
- Relatively few flights which can easily cause negligence or reduced vigilance amongst passengers and staff, including but not limited to pilots leaving passengers unattended, passengers roaming freely, vehicles unequipped with radio or the radio not being used, etc.
Runway Incursion Prevention Strategies
Runway incursion prevention strategies should be in place to encompass all potential aerodrome staff, users and visitors. Some of the mitigation strategies are as follows:
When people are required to work out on an aerodrome,and particularly on the runway, they should:
- Be clearly visible at all times.
- Be provided with a radio.
- The radio must be checked for functionality and frequency selection.
- The user should, at all times, listen out for traffic but also be aware that not all aircraft use radio.
- Where possible, work in pairs and proceed against the aircraft traffic direction to improve lookout.
- Understand the terms pilots use to describe runways, taxiways, aircraft position on the ground and in the air in the proximity of the aerodrome
- Be familiar with the relevant rules and regulations
- Be aware of:
- Low visibility of aircraft due to size, weather conditions, and sun position.
- Quietness of aircraft conducting glide approaches.
- The directions from which an aircraft may approach.
- The pilot’s reduced ability to steer the aircraft and to see when the aircraft is on the ground, particularly in the case of tail wheel aircraft.
Runway crossings should be limited, or better still, prevented. This can be done by:
- Providing routes around a runway or alternative access to the aerodrome site.
- Providing physical barriers along with good signage around and on the aerodrome to prevent vehicles straying onto runways and taxiways.
- Controlling the number of vehicles permitted.
- Ensuring all drivers are aware of the rights-of-way described in the relevant national documents.
The aerodrome owner/manager should consider the aerodrome from the perspective of an unfamiliar visiting or student pilot by:
- Ensuring all runway holding positions are clear to pilots in the approaching directions, noting that different aircraft types present different height and viewing perspectives.
- Implementing clear, simple taxiway layouts and junctions of 90° shown by grass cut heights to avoid confusion.
- Limiting runway access and the width of any access points to reduce the possibility of pilots accidentally entering a runway.
- Positioning a runway access point so that it provides clear views of both approaches, ideally at 90°; consider any slope or obstacle issues to reduce the risk of conflict.
- Making sure that all runway access point approach views are regularly checked and maintained.
- Ensuring the AIP shows the correct aerodrome layout, if applicable.
Visitors (and passengers) may be unaware of the possible dangers. To avoid the risk of getting hurt or causing others to get hurt they should follow the rules as written on the aerodrome signs as well as the instructions of pilots and aerodrome staff. To help protect the people the aerodrome owner/manager should:
- Ensure the aerodrome boundary is secure, and access is controlled.
- Consider signage at the boundary of a licensed aerodrome clearly indicating there is no access without permission. Signage may quote a relevant regulation to discourage trespassers.
- Where there is access, in particular a public rights of way, provide signage that clearly warns of the dangers such as approaching aircraft which may be difficult to see if there is any ground slope, obstacles, or (nearly) silent aircraft practising glide approaches. Signage should also indicate from where aircraft will be approaching and advise that some pilots may have reduced vision and steering ability whilst conducting taxy operations.
- In cases of public right of way, additionally consider providing a clearly signed alternative route.
- Clearly define areas where dogs are required to be kept on leads. Under certain legal circumstances and with permissions, stiles can be used to restrict animal access.
- Remind pilots that their passengers should be escorted and supervised at all times whilst on the aerodrome. This may be published in the local flying orders, noted in the AIPs or presented on aerodrome signage.
- Ensure the security of the aerodrome boundary and the associated signage is inspected regularly.