LBT PROJECT
2x8,4m TELESCOPE
Doc.No. : 650s
Issue
:a
Date
: 05 Oct 2012
LBT PROJECT
2 X 8,4m OPTICAL TELESCOPE
Use of Aircraft Spotters for Laser Safety
Prepared
Reviewed
Released
Signature
Gustavo Rahmer
Date
19-Oct-2012
Use of Aircraft Spotters for Laser Safety
Doc.No : 650s
Issue
:a
Date
: 19-Oct-2012
Page 2
1. Revision History
Issue
a
Date
19-Oct-12
Changes
Issue a.
Responsible
Gustavo Rahmer
Use of Aircraft Spotters for Laser Safety
Doc.No : 650s
Issue
:a
Date
: 19-Oct-2012
Page 3
2. Table Of Contents
1.
2.
3.
3.1.
3.2.
3.3.
4.
5.
5.1.
5.2.
5.3.
6.
6.1.
6.2.
7.
7.1.
7.2.
8.
8.1.
8.2.
8.3.
8.4.
9.
9.1.
9.2.
9.3.
Revision History ......................................................................................................... 2
Table Of Contents ....................................................................................................... 3
About this document ................................................................................................... 4
Purpose .................................................................................................................... 4
Reference Documents ............................................................................................. 4
Acronyms ................................................................................................................ 4
Aircraft Safety Personnel ............................................................................................ 5
Spotter Qualifications and Training ............................................................................ 5
Visual Exams .......................................................................................................... 5
Training ................................................................................................................... 5
Spotter Stations ....................................................................................................... 5
Spotter Gear ................................................................................................................ 5
Communications ..................................................................................................... 5
Cold Weather Gear ................................................................................................. 5
General Procedures ..................................................................................................... 6
Breaks ..................................................................................................................... 6
Standing Down........................................................................................................ 6
Preparing for Operations ............................................................................................. 6
Communications Test ............................................................................................. 6
Remote Control Test ............................................................................................... 6
Dark Adaptation ...................................................................................................... 6
Immediately prior to propagating ........................................................................... 6
Normal Operating Procedures..................................................................................... 7
Reporting to Laser Safety Lead .............................................................................. 7
Safety Buffer Size ................................................................................................... 7
Communication protocol ........................................................................................ 7
9.3.1.
All clear before propagation begins ............................................................ 7
9.3.2.
Intermittent shutdowns................................................................................ 7
9.3.3.
Thresholds for various types of reporting ................................................... 7
9.3.4.
Reporting on Weather ................................................................................. 8
10.
System Failures or Partial Failures ......................................................................... 8
Use of Aircraft Spotters for Laser Safety
Doc.No : 650s
Issue
:a
Date
: 19-Oct-2012
Page 4
3. About this document
3.1. Purpose
The purpose of this document is to present the plan for use of aircraft spotters as part of
our laser safety program.
3.2. Reference Documents
[RD1] ANSI Z136.6 Standard for Safe Use of Lasers Outdoors
3.3. Acronyms
ARGOS
LSO
Advanced Rayleigh guided Ground layer adaptive Optics System
Laser Safety Officer
Use of Aircraft Spotters for Laser Safety
Doc.No : 650s
Issue
:a
Date
: 19-Oct-2012
Page 5
4. Aircraft Safety Personnel
This section describes the roles and responsibilities of the personnel involved in our
aircraft safety approach during the operation of the laser system.
5. Spotter Qualifications and Training
Aircraft spotters must be properly qualified and trained as described below.
5.1.
Visual Exams
Aircraft spotters are required to pass a visual exam. Aircraft spotters must have at least
20/20 corrected vision, normal visual fields and no pathology of the eye. We also require
that aircraft spotters have normal color perception, at least to the extent that they can
make use of the red and green lights on aircraft to determine the direction of travel.
5.2.
Training
Spotters are trained regarding applicable responsibilities and procedures per ANSI
Z136.6 - 2000 appendix F, section 7. Personnel receive training on specific hazards of
lasers used, methods of communications with appropriate control centers and authorized
laser operators, emergency laser shutdown, and pertinent regulations. This includes
training in: Assigned duties and responsibilities; local safety procedures; local emergency
laser termination procedures; laser hazard identification; local air traffic patterns; visual
scanning techniques; and limitations of the observing location.
5.3.
Spotter Stations
Aircraft spotters will be positioned to have a clear unobstructed view of the affected area
and have access to a shut off device.
6. Spotter Gear
6.1.
Communications
The spotter will be in voice contact with the Laser Operator by means of a two-way radio.
The spotter work station will have a predetermined “call sign” for use in
communications.
6.2.
Cold Weather Gear
To protect the spotter from the harsh summit conditions, spotters will be provided with
adequate cold weather gear.
Use of Aircraft Spotters for Laser Safety
Doc.No : 650s
Issue
:a
Date
: 19-Oct-2012
Page 6
7. General Procedures
7.1.
Breaks
To mitigate the effects of boredom, distraction, fatigue and the harsh environment, the spotter will
work outside watching for aircraft one hour on, with 50 minutes off, and a 10-minute time for
dark adaption of their eyes.
7.2.
Standing Down
During laser down time, the Laser Safety Lead will make a decision whether to have the
aircraft spotter come inside or not. If the down-time is expected to be short (less than 15
minutes) it may be more efficient to have the spotter remain outside during the down time
to avoid the need to dark adapt their eyes again.
In the event the aircraft spotter is called in, the Laser Safety Lead will make a clear and
definitive announcement via the spotter communication system:


“Aircraft spotters stand down for XX minutes,” or
“Aircraft spotters stand down. We are done for the evening.”
8. Preparing for Operations
8.1.
Communications Test
Prior to evening operations, and for relocation to a different spotter station, the spotters
will test their communication devices to ensure that they are fully functional.
8.2.
Remote Control Test
Prior to evening operations, each spotter will test their remote control to insure that it is
fully functional. This test will be performed in coordination with the Laser Operator.
8.3.
Dark Adaptation
The spotters will go to their designated work station at least 10 minutes before they are
needed in order to ensure that spotter’s eyes are adjusted to the dark. This includes shift
changes during the night as well as the first shift of the night.
8.4.
Immediately prior to propagating
At the beginning of the night, or when laser emission is about to continue after a period
of non-use, the following exchange will take place:

At least 10 minutes prior to laser emission, the Laser Operator will announce
on the radio “Aircraft spotters to report stations”, at which time the aircraft
spotters will proceed to the assigned spotter stations.
Use of Aircraft Spotters for Laser Safety

Doc.No : 650s
Issue
:a
Date
: 19-Oct-2012
Page 7
Upon arriving at the stations, the aircraft spotters will check in to the Laser
operator via radio with “Spotter 1 on station” or “Spotter 2 on station.”
9. Normal Operating Procedures
9.1.
Reporting to Laser Safety Lead
The spotters will report potential hazards of any kind within visual range to the Laser
Operator.
9.2.
Safety Buffer Size
The spotters will request termination of laser propagation for any aircraft that approaches
to within 25 degrees of the beam. This allows adequate time before an aircraft could
intersect the beam.
9.3.
Communication protocol
9.3.1. All clear before propagation begins
When desiring to propagate the laser, the Laser Operator will poll the spotters giving the
direction of expected propagation:

“Attention spotters, we request that you confirm if it is clear to propagate
toward the north at an elevation of 50 degrees and an azimuth of 15 degrees.”
If no aircraft or clouds that would prevent spotting aircrafts are within the angle of the
requested propagation direction, the spotters should answer in turn:


“This is Spotter 1. You are clear to propagate in the specified direction”
“This is Spotter 2. You are clear to propagate in the specified direction”
From this moment on, the spotters must watch the direction stated and report any aircraft
and clouds whether or not the laser is propagating.
9.3.2. Intermittent shutdowns
If the laser is being shuttered for more than 30 seconds, then the Laser Operator considers
the permission to propagate “stale” and again requests permission to propagate from the
spotters.
9.3.3. Thresholds for various types of reporting
Two zones are defined:
1. “Warning Zone”: A circle around the beam with a radius of 50 degrees.
2. “Danger Zone”: A circle around the beam with a radius of 50 degrees.
As reference, a full hand span measures about 20 degrees.
Use of Aircraft Spotters for Laser Safety
Doc.No : 650s
Issue
:a
Date
: 19-Oct-2012
Page 8
The spotters will report all aircraft to the Laser Operator via radio, with the following
protocol:

Aircrafts greater than 50 degrees from the beam.
The time of sighting, elevation, heading and direction of sighting, will be
recorded by the Assistant Spotter into a nightly log.

Aircrafts within 50 degrees of the beam (“Warning Zone”)
“This is Spotter 1. We have an aircraft in the area, within 50 degrees of the
beam. Not a factor at this time. I will keep you posted.”

Aircrafts within 25 degrees of the beam (“Danger Zone”)
“This is Spotter 2. There is an aircraft inside the danger zone. I request laser
to be shuttered. I will report when the aircraft clears the area.”
The spotter should press the kill button on the remote control the laser is still
on after the request, and the aircraft is still in the danger zone.

When a previously reported aircraft leaves the 25-degree safety buffer.
“This is Spotter 2. The beam path is clear. You may enable the laser.”
9.3.4. Reporting on Weather
The spotters will report weather conditions to the Laser Operator that prevent effectively
spotting aircraft visually, using the following language:

If there are thick clouds greater than 25 degrees from the beam.
“This is the Spotter 1. Clouds are threatening to obstruct my view. I will keep
you posted.”

If thick clouds are within 25 degrees of the beam, preventing the spotter from
seeing beyond the clouds.
“This is the Spotter 2. I request you shutter the laser due to cloud cover. I will
inform you when clouds clear and beam path is clear.”

If there are thin clouds that could be illuminated by the laser and potentially
affect adversely the observation.
“This is Spotter 1. There are clouds in the vicinity of the laser beam. I will
keep you posted.”
10. System Failures or Partial Failures
Failure of a required component of the safety systems shall result in the abort of any laser
propagation until corrected.
Use of Aircraft Spotters for Laser Safety
Doc.No : 650s
Issue
:a
Date
: 19-Oct-2012
Page 9
If the laser beam failed to shutter and a reflection was seen from the aircraft, the Laser
Operator shall be immediately notified. The Laser Operator shall immediately notify
management and the LSO. Management shall immediately notify the required
organizations. An incident report is to be completed.