Air Traffic Bulletin

Issue 99-2 Spring 1999

Table of Contents: [Back]
Clear of the Runway
TCAS Advisories
Expeditious Compliance
Runway Exiting or Taxi Instructions
Land and Hold Short Operation(LAHSO) Clearance
    A Few Wrongs Won't Make it Right, or Something Like That...
    Who's in Charge?

Clear of the Runway

/*T/ Several recent incidents and inquiries indicate that we should review the subject of "Clear of the Runway." Referring to the Pilot/Controller Glossary, "Clear of the Runway" is broken into three parts:

Part a - describes a taxiing aircraft approaching a runway. To be clear of the runway in this scenario, the aircraft must hold short of the applicable holding position marking. If an aircraft crosses that hold line, it is in the runway environment and, therefore, the runway cannot be considered clear.

Part b - describes an aircraft exiting the runway after landing or crossing a runway. In this situation, an aircraft is considered clear of the runway when the entire airframe clears the runway edge and there is no ATC restriction to its continued movement beyond the applicable holding position marking.

Part c - of this definition gives pilots and controllers some issues to consider to ensure adequate separation will exist when inadequate runway edge lines or holding position markings are present.

In addition to reviewing "Clear of the Runway," FAAO 7110.65, Paragraph 3-10-9, Runway Exiting, should also be reviewed as it ties directly to Part b of the definition of "Clear of the Runway." Local and ground controllers must be constantly vigilant of aircraft exiting the runway by clearing the hold position marking associated with the landing runway and ground traffic in close proximity to the exiting aircraft. This is an important time for good teamwork and preplanning in order to avoid incidents or unexpected tie ups at a critical point on the surface. >(ATO-100)

TCAS Advisories

/*TE/ Reports by system users suggest that controllers are advising pilots during certain traffic situations that a TCAS alert may be received. While this information may seem beneficial to the flow of traffic, controllers should be aware that these transmissions will not necessarily avoid action by pilots in response to an alert as company operating policies require certain responses. FAAO 7110.65, Paragraph 2-1-21, Traffic Advisories, should give sufficient guidance for phraseology during traffic situations, and addressing TCAS in the message may cause unnecessary distractions in the cockpit.

Traffic advisories are an important part of controller/pilot communications. Traffic should always be issued when in the controller's opinion the proximity of the aircraft warrants it. Always include in these transmissions the azimuth or direction from the aircraft and the distance, the direction the traffic is moving, and the type and altitude of the traffic, if known. (ATO-100)

Expeditious Compliance

/*TE/ FAAO 7110.65, Air Traffic Control, defines two types of expeditious compliance:
Immediately - Use the word "immediately" only when expeditious compliance is required to avoid an imminent situation.
Expedite - Use the word "expedite" only when prompt compliance is required to avoid the development of an imminent situation.

In either case, if time permits, the specialist should include the reason for using the expeditious clearance.

Controllers should keep in mind these important points when using "expedite" as part of a clearance:
Expedite climb/descent normally indicates to a pilot that the approximate best rate of climb/descent should be used without requiring an exceptional change in aircraft handling characteristics.
The term "expedite" should not be overused. The effectiveness of the clearance may be diluted unless it is used only when needed. (ATO-100)

Runway Exiting or Taxi Instructions

(This article originally appeared in Bulletin 98-3)
/* T/ Taxi instructions are something we are all familiar with and issue hundreds of times a day. Although there is no definition in the Pilot/Controller Glossary that defines "taxi instructions," taxi is the movement of an airplane under its own power on the surface of an airport.

Recent feedback from our users indicates we may have become complacent about when we issue taxi instructions, especially to landing aircraft during the critical phase of operation immediately after touchdown.

During the touchdown and deceleration of an aircraft, the workload in the cockpit is extremely high, as is the noise level. It is possible that a control instruction like, "Turn left at highspeed Tango, hold short of Runway 12 and contact ground on 121.7," may be misheard or misunderstood and result in a serious incident. Although it is impossible for any controller to know what is happening in the cockpit or to effectively assess what is a "critical phase" of the flight, every effort should be made not to issue instructions at this point in the flight.

Unless a duty of higher priority dictates, we should attempt to avoid issuing taxi instructions during critical operations such as immediately after landing. When to issue that instruction must rest with the judgment of the controller after considering factors which may include, but are not limited to, aircraft type, configuration, and speed, as well as the landing environment (including existing weather and runway conditions). These variables represent subjective observations and a controller is expected to use prudent judgment. (ATO-120)

Land and Hold Short Operation(LAHSO) Clearance

(This article originally appeared in Bulletin 98-3)
/*T/ Air traffic controllers have been conducting Land and Hold Short Operations (LAHSO) since 1968. Until July 17, 1997, LAHSO's were conducted to intersecting runways only and that procedure was referred to as Simultaneous Operations on Intersecting Runways (SOIR). Prior to July 17, 1997, there were a few locations that were authorized to land and hold short of a taxiway or approach path.

Feedback from our users indicates that, occasionally, LAHSO clearances have been refused by the pilot and the refusal has been questioned by the controller. Please remember that the pilot is directly responsible for, and is the final authority concerning, the operation of an aircraft, and depending on several variables, may not be able to accept this type of clearance. FAAO 7110.114 clearly defines that when LAHSO's are expected to be utilized, an announcement shall be made on the Automatic Terminal Information System or pilots shall be advised on initial contact or as soon as practicable thereafter to expect a LAHSO clearance.

If the requirements of the user or pilot prevent the acceptance of a LAHSO clearance, it is the responsibility of the pilot to inform ATC as soon as possible. (ATO-120)


Learn from the mistakes of others.
You won't live long enough to make all of them yourself.


A Few Wrongs Won't Make it Right, or Something Like That...

A B737 nearly collided with a C-210 in the intersection of two runways while both aircraft were on takeoff roll. The incident occurred when the C-210 pilot took the takeoff clearance that had been issued to the B737. The B737 pilot saw the C-210 at the last moment and jerked his aircraft's nose into the air to fly over the other aircraft, missing a collision by less than an estimated 100 feet. In the aftermath of the investigation some interesting points came to light. The following is a dissection of the incident which examines all of the links that made up the chain of events leading to the pilot's mistake.

It is indisputable that the cause of the near collision was a pilot deviation committed by the C-210 pilot. What is interesting are the links in the chain provided by factors other than the pilot himself.

THE PILOT: An elderly gentleman traveling with two licensed pilots. Received his pilot license in 1994. Had been involved in a runway incursion at another controlled general aviation airport due to misheard instructions.

THE ATCS: Full performance level certified on the local control position since 1997. Had been involved in an operational error within the past 21/2 years where an arrival had been permitted to land over another aircraft on the runway.

THE AIRPORT: Runway configuration of 31L/13R that crossed runway 35/17. Runways 35 and 31L were in use.

THE WEATHER: Ceiling 300 ft. overcast with visibility of 2 1/2 miles in mist

Building the links in the error chain ----

1.  SWA553 is instructed to taxi into position and hold on runway 31L.
2.  N9963Y is instructed to taxi into position and hold on runway 35.
3.  The ATCS cannot see the aircraft due to the poor visibility.
4.  The facility is not equipped with Airport Surveillance Detection Equipment (ASDE).
5.  Both pilots are expecting takeoff clearance but are not aware of each other.
6.  The ATCS does not state the runway number when issuing the takeoff clearance to SWA553.
7.  The ATCS's phraseology may have inadvertently created a similar sounding call sign.
8.  When SWA553 is issued takeoff clearance, his somewhat lengthy response masks the C-210 pilot's read back of the same takeoff clearance.
9.  The C-210 pilot does not depart immediately. He pauses to check his directional gyro and other instrument settings before adding power for the takeoff run. He uses "most of the runway" before liftoff.

It is chilling to consider the many "what-ifs" associated with this incident. Could this incident have been prevented?

The decision to put both aircraft into position and hold on runways that crossed in visibility conditions where neither pilots nor controller could affirm who was doing what could be criticized in this situation. Although not prohibited by regulation for civil aircraft, the stage was set with two aircraft poised for departure. Neither crew was specifically advised that another aircraft was holding in position on a crossing runway.

The C-210 pilot's inattention to the controller's instructions must also be criticized but a key to this incident is the controller's choice to use non-standard phraseology. This decision helped to forge the links of the chain of events.

The ATCS did not state the runway's name when issuing the takeoff clearance. Could this have clued the C-210 pilot that the takeoff clearance was not for him? The ATCS also referred to SWA553 as "Southwest five, five, three" instead of Southwest five-fifty-three as is required by FAAO 7110.65 Paragraph 2-4-20. This may seem like a petty criticism at first glance, but if you think about it, you'll realize that the ATCS inadvertently created a similar sounding call miscommunication. Although the words are quite different, the sounds are very similar. (The similar sounds are highlighted in bold print to assist in identification.)

The ATCS stated, "Southwest 5-5-3 heading 3-1-5 cleared for takeoff."
The Cessna pilot heard, "Cessna 9-9-6-3 yankee runway 35 cleared for takeoff."

If the pilot is not paying close attention or has not been cued to pay attention, the clearance as stated sounds like what the pilot is expecting to hear. Hearing clearly is also hindered by background noise produced by his engine, propeller, the "oil canning" vibration of the aircraft's body, ambient conversations of his passengers, and his anticipation of the magic words, "cleared for takeoff."

Standard phraseology provides enough of a difference that if the ATCS had chosen to use it, the C-210 pilot may not have been as likely to mistake the clearance for his own. "Southwest five fifty-three, turn right heading 3-1-5, runway 3-1 left, cleared for takeoff."

Using the correct phraseology in and of itself is not the final cure for such incidents. What was said, how it was said, as well as what was not said were only a few links in the chain. The pilot's inattention, the weather conditions, both aircraft placed in position and holding on crossing runways, all contributed the links that made up the chain. In this case, no one broke the series of link building. In this case, the hapless pilot forged the last and almost lethal link.


Who's in Charge?

A Part 121 carrier dispatcher called an air traffic facility on the phone to inquire about the status of a particular flight. The dispatcher was told that the flight had executed a missed approach due to a traffic conflict. The dispatcher told the facility that the flight should now be considered in a "minimum fuel" status. The facility representative said to the dispatcher, "That's not your call, that's up to the pilot." Was the facility representative correct?

FAR 121.533 Responsibility for Operational Control: Domestic Operations, states, "The pilot in command and the aircraft dispatcher are jointly responsible for the preflight planning, delay, and dispatch release of a flight."

FAR 121:535 states, "The aircraft dispatcher is responsible for monitoring the progress of each flight; issuing necessary information for the safety of the flight; canceling or re-dispatching a flight, if, in his opinion or the opinion of the pilot in command, the flight cannot safely operate or continue to operate safely as planned or released. Each pilot in command of an aircraft is, during the flight time, in command of the aircraft and crew and is responsible for the safety of the passengers, crewmembers, cargo, and airplane."

FAR paragraph 121.557 gives broad authority to the pilot in command of the flight to preserve safety during an emergency situation. Here is what it says regarding the flight dispatcher's authority and responsibility. "In an emergency situation arising during flight that requires immediate decision and action by an aircraft dispatcher, and that is known to him, the aircraft dispatcher shall advise the pilot in command of the emergency.. If the aircraft dispatcher cannot communicate with the pilot, he shall declare an emergency and take any action that he considers necessary under the circumstances. Whenever a pilot in command or dispatcher exercises emergency authority, he shall keep the appropriate ATC facility and dispatch centers fully informed of the progress of the flight."

The Flight Ops Manual reference for one particular airline states: "When a minimum fuel condition exists, the dispatcher shall contact the appropriate ATC facility and ensure that communication and coordination among the pilot, dispatcher, and ATC continue until the flight has landed safely."

Although minimum fuel status is not an emergency situation, it is well within the purview of the flight dispatcher to inform ATC that the flight should be considered in minimum fuel status. The dispatcher is in a good position to know because the dispatcher approved and decided how much fuel the flight would leave with in the first place, and he received fuel burn reports en route. Flight crew and dispatcher work together as a team. Respect that team effort. (AAT-210)


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