Aviation security, like flight safety - comprises multiple layers. The principle being that when any one layer is breached, a subsequent layer will maintain the safety of the system. Ultimately, national governments control the airspace in which we fly, and most have forces available to secure that airspace. A meeting of the ECA Security Group has just reviewed recent cases where civil aircraft have been intercepted by the military - albeit unnecessarily - within European airspace.
The military's first intention - having intercepted your aircraft - will be to ascertain that your flight deck is 'secure' (any doubt would have been 'key' in the authorities decision to 'go' for your interception in the first place). Your intention should be to indicate to the interceptor/authorities, that your flight deck is and remains secure, as quickly and as clearly as possible.
Some of the things to bear in mind if intercepted are:
- That you should comply with instructions given by the intercepting aircraft - responding to visual signals as required.
- Notify the appropriate ATS unit of your interception (if all has gone to plan, they should already be involved) and importantly - try to notify your company, so that its 'assessor' can liaise with the authorities. The latter can be key to a safe and early withdrawal of intercepting aircraft.
- Attempt to establish radio communication with the intercepting aircraft by making a general call on 121.5, giving your call sign, nature of flight and intentions. (It's well worth refreshing your memory of ICAO standard interception procedures and signals).
Intercepting aircraft are under strict instructions to avoid manoeuvres, which could alarm those on board an intercepted aircraft. However, they will need to encroach on standard vertical separation to check that your flight deck is secure. They may therefore switch off their mode C transponders.
If not, it is possible that an intercepted aircraft, operating at its operational ceiling intercepted from below, would receive a TCAS climb RA - nor does it allow for a situation where an aircraft continues to climb as it intends to intercept you - you could end up visiting areas of the flight envelope normally reserved for test pilots.
Interception from above could lead to a continuous TCAS descent - either scenario could appear to be an apparent evasive manoeuvre to any interceptor. Should you be aware that you are about to be intercepted - it could be prudent to select your TCAS to TA only.
The ECA Security and ATS Groups are currently working with ICAO on the revision of its Manual for Interception of Civil Aircraft (MICA). The ECA Security Group also participates in NEASCOG (NATO-Eurocontrol ATM Security Co-ordinating Group) and SAGAS (Stakeholder Advisory Group for Aviation Security) which work towards the reduction of, and protocols for Air Intercepts in Europe.
BALPA, ECA Security Group member