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Offshore Notebook: Fighter Intercepts Along the ADIZ

By By Pat Gray | September 1, 2012
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Long before TFRs became so commonplace, those of us who made our living flying in the Gulf of Mexico had, and still have, a flight restriction called the Air Defense Identification Zone (ADIZ). The responsibility for, and response to protecting American real estate from any form of flying mayhem aimed at harming our homeland, rests with the assets of the North American Aerospace Defense Command (NORAD). The 601st Air and Space Operations Center (AOC) at Tyndall Air Force Base in Florida is a huge part of this umbrella. The AOC commander, Col. Randy Spear, states that the 601st is also a major part of the Domestic Event Network (DEN) comprised of the FAA, DoD, Secret Service, TSA and some others. This is a very large communications network that covers the entire U.S. and allows almost instant communication between the various agencies. If you are a helicopter pilot it is not good to become a topic of conversation within that net.

The Airman’s Information Manual, along with some other documents, gives very clear and definitive procedures for ADIZ penetration for inbound flights. Voice communication and transponder equipment are the two “must have” basics for flying in, around or through the ADIZ. Seems simple enough. Just make sure to file a flight plan when inbound to the U.S. and provide appropriate information on routes, tail number, time of penetration, altitudes and so on.

Now let’s make it more complicated. Place 500-plus helicopters in the north side of the Gulf of Mexico on any given day. Most of them are VFR flights without FAA flight plans. (There is a small percentage that are IFR and those do have a flight plan.) Let’s suppose half of them will be going in and out of the ADIZ multiple times in a day. One helicopter could make as many as 15 penetrations a day. The need is there because a large number of the oil rigs are outside of the ADIZ. It’s easy to imagine the confusion and delays that would be involved if all 250 or so helicopters had to file a flight plan for each inbound flight.


So, how is it handled? FAA issues a discreet transponder code for each individual commercial operator flying in the gulf and waives the need for an FAA flight plan. No problem, almost all of the helicopters are on a company flight plan and are flight followed by their company. These codes are proprietary for each company and once activated, they identify the aircraft as belonging to that company. The codes are frequently changed to prevent being compromised.

There is always the potential for a problem to arise using the system. When the helicopter leaves its base in the morning, the pilot is required to squawk a VFR 1200 code and usually when crossing the beach outbound, he/she will switch to the discreet code for his company and keep it on for the duration that he is over water, even if there’s no requirement to go through the ADIZ. The problem arises when the pilot forgets to change to the discreet code and continues outbound and through the ADIZ or, after landing at an intermediate stop, fails to turn the transponder on, enters a wrong code or in rare instances, has an avionics failure. To my knowledge, there are no bells and whistles to remind the pilot to switch codes. When he drops the passengers and returns, penetrating the ADIZ inbound, the helicopter becomes an unidentified target. This violation now becomes the concern of the 601st AOC. The helicopter is now lighting up radars from Corpus Christi to Miami. Because of the slow airspeed and proximity to the oil fields, efforts will be made by the military and the FAA—via telephone—to identify the pilot. There are no assumptions. Usually they resolve the mystery and can identify the commercial operator the helicopter belongs to and that company’s dispatchers will take care of the problem.

Year in and year out there is always a percentage that do not get identified through whatever means, therefore NORAD is forced to launch interceptors, either F-16 or F-15 fighter jets. These Air Force jets, normally in pairs, will rendezvous with the errant helicopter, record the tail number and company and return to base, write up an action report and send it up through channels. Of course the bad actors (drug smugglers, etc.) would be handled differently.

Over the past four years there have been more than 40 scrambles for oil field helicopters. There can be several stages of actions related to a scramble some of which will not necessarily result in a flight. It can be exciting for a slow-mover to find a pair of Mach 2 fighters flying in formation with him. In the interests of safety, I remember years ago, during a helicopter meeting with the NORAD pilots, someone asked if it would be possible for the fighters to escort the helicopters using 500 feet per minute climbs and descents. When the dead silence was broken, the fighter pilot replied: “Sir, we do not do anything at 500 feet per minute.” Keep your transponders on and the discreet code active!

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