Overdue Aircraft | The Three Phases of Search and Rescue

Overdue PLANE

Any time an aircraft may be overdue, missing, as results, the search and rescue plan is activated. An aircraft on a flight plan is considered overdue when it has failed to arrive at its destination, compulsory reporting point, clearance void time or clearance limit 30 minutes after its estimated time of arrival and communications or location cannot be established. But in case of overdue aircraft (no flight plan), it is considered overdue when at the actual time a reliable source reports it to be at least 1 hour late at destination.


In this article, I am going to give you an idea about how the FAA search and rescue plan is activated. Before starting, you need to distinguish between these two key words, search and rescue.

What does the term search and rescue mean? 

If rescue personnel don't know where the aircraft is, it's a search. If the they do know where the aircraft is, then it's a rescue. in this context, responsibility can be broken down into two different areas:

1- The aircraft location is not knowing

In this case, it is the pilot's responsibility to tell search and rescue team by flight plan or radio call. furthermore, after plane crash, it is the aircraft crew responsibility to tell the search and rescue team where they are by using of emergency locator transmitter (ELT) or ground to air signals. 

What aircraft crew do to help in the search phase is the key to their survival, shorten the time from the crash to rescue.

Note : You may like to read my article titled "How Aircraft Crew Deal with the 9 Mental Stressors Successfully".

2- The aircraft location is knowing

If search and rescue team know where the aircraft location is, then it's aircraft crew and the rescuer's responsibility to  passengers home.

Note : You may like to read my article titled "Why Passengers & Crew Should Assume an Appropriate "Brace-for-Impact Position"".

Average Time from LKP to Rescue Overdue Aircraft

Flight plan

Average Time

If the aircraft use Instrument Flight Rules (IFR)

=11.5 Hours

If the aircraft use Visual Flight Rules (VFR)

= 18 Hours

If the aircraft use No Flight Plan

= 62.5 Hours

Source : FAA/Basic Survival Skills for Aviation

Flight plan

Average Time

If the aircraft use Instrument Flight Rules (IFR)

=13 hours 6 minute

If the aircraft use Visual Flight Rules (VFR)

= 37 Hours 18 minute

If the aircraft use No Flight Plan

= 42 hours 24 minutes

 Source: FAA/pilot/training

Note : PILOTS :Having a flight plan on file with a flight service station is very important.

How much longer?

By filing a flight plan by pilots, it takes a shortest time for rescue team to accomplish the survival goal " rescue". The types of flight plan filed will greatly affect the time. As a result, aircraft crew and passengers may have to survive during a search phase.

No matter how long aircraft crew and passengers stayed in the crash place, the important thing is that they should do everything in their power to accomplish the survival goal.


When is an Aircraft overdue?

For an aircraft on a flight plan, the air traffic control system will automatically initiate a plan to locate overdue aircraft. When an aircraft on a VFR flight plan is overdue by 30 minutes , or by 30 minutes on a IFR flight plan, the Flight Service Station servicing the destination airport issues an INREQ (Information Request).

For an aircraft (no flight plan), there is no designated time limit before a search is initiated, thus greatly delaying the onset of search and rescue.

Searching for Overdue Aircraft - the Process 

Even though an aircraft is missing the search may not initiate immediately. The aircraft must first be verified as overdue. This step of the process is dictated by the type of flight plan the pilot in command filed. An Information Request (INREQ).is filed by the Flight Service Station servicing the destination airport when:

An aircraft flying IFR is overdue with no communications 30 minutes after ETA to a reporting point. This may be to an enroute point or destination.

- An aircraft flying VFR is overdue by 30 minutes after ETA to final destination. NOT to an enroute fuel stop, detour, etc.

- An aircraft filing no flight plan is overdue by one hour, as reported to the FAA by a reliable source


Once the aircraft has been verified to be overdue the first of three phases is initiated.

First Phase:  The Uncertainty Phase.

During this phase the FAA and the AFRCC " Air Force Rescue Coordination Center" conduct a preliminary Communications (PRECOMM) search. Because of the high rate of false alarms, this phase is designed to see if the situation is really a missing aircraft or a pilot who didn't close a flight plan. If the PRECOMM comes up negative, then the next phase is activated.

What is INREQ (Information Request)?

It is done within 30 minutes after the aircraft is overdue which destination airfield allowed to send INREQ. It is sent to the departure airfield, FSS, and the Air Route Traffic Control Centers along the route of flight.


Second Phase:  The Alert Phase or Alert Notice (ALNOT).

Normally the ALNOT is issued at the end of INREQ, at the estimated time that the aircraft fuel would be exhausted, or when there is serious doubt as to the safety of the aircraft and occupants. During the ALNOT, the destination airport checks all ramps and hangars to locate the aircraft. Local law enforcement in the search area is notified, and all information is sent to AFRCC. If the aircraft is not found during the ALNOT then the third and final phase is activated.

What is ALNOT (Alert Notice)?

 ALNOT t is "a request originated by a flight service station (FSS) or an air route traffic control center (ARTCC) for an extensive communication search for overdue, unreported, or missing aircraft," 

 Conduct a communications search of those flight plan area airfields, which fall within ALNOT search areas and were not contacted during an INREQ search.


Third Phase:  The Distress Phase

At this point, the actual search mission is launched. Usually, air search efforts will not begin until daylight, unless the aircraft is equipped with a functioning ELT (Electronic Locator Transmitter) directing a ground rescue party to the general vicinity of the aircraft crash site, and if, the weather permits, an ELT also points air rescue to the distress location. Even with a functioning ELT, terrain and weather may hamper response time.

Aircraft crew should remember that survive after a crash needs a good training and good survival kit.

Thank you for reading. Could you please tell 3 of your friends about aviation-professional.net.

Maged Saeed AL-Hadabi

I’m Instructor / Maged Saeed Al-Hadabi. ​ Air Cargo / IATA Dangerous Goods Regulations / Safety Management System Senior Instructor, Auditor [ Yemen Airways] . Approved IATA DGR/ SMS Instructor by Yemen Civil Aviation Authority.

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