From the COPA website...

Electronic warfare effects flight safety - Beware in Ontario and Quebec
in June!

While preparing for a trip from Ottawa recently, COPA staff member Adam
Hunt noticed the following NOTAM in the Flight Information Region
section of the NOTAMs:

040305 CZUL MONTREAL FIR
CZUL GPS JAMMING EXERCISES MAY RESULT IN INTERMITTENT LOSS OF GPS
SIGNALS IN VICINITY OF 4539.8N 7736.2W (YXI VOR) FROM 350 RADIAL
CLOCKWISE TO 090 RADIAL. AFFECTED AREA EXTENDS TO 100 NM BELOW
3000 FT MSL, AND UP TO 250 NM ABOVE 3000 FT MSL. GPS APCH NOT
AUTH AT PEMBROKE (CYTA), MANIWAKI (CYMW) AND MONT-LAURIER (CSD4)
DURING EXERCISE PERIODS 1400-1900 DAILY 0406091400/0406111900
AND 1400-1900 DAILY
0406141400 TIL 0406151900

Given the proximity of the jamming to some of the busiest flying areas
in Canada and the potential for the directional jamming to go beyond
the intended direction, COPA President Kevin Psutka contacted key
individuals at the Department of National Defence (DND), Transport
Canada and NAV CANADA and also made our sister organization, AOPA US,
aware of our concerns.

In a strongly worded message to the agencies, COPA emphasized that
there is a flight safety trap being created by this exercise, most
notably that they intend to proceed with the exercise even if the
weather is IFR, when potentially someone will use GPS as the primary
means of navigation. We pointed out the FIR NOTAMs are more obscure and
sometimes difficult to decipher.*It is very likely that, despite the
length of time that the NOTAM will have been in effect by the time the
jamming exercise takes place, there will be a significant number of
pilots in Canada using GPS during the period that the jamming will
occur who will not be aware that jamming is occurring.

From the location information in the NOTAM, it is not clear where the
jamming will be coming from, so DND was contacted for more information.
It will in fact come from Canadian Forces Base Petawawa, north-west of
Ottawa. Besides the obvious question regarding the need to actually jam
versus simulate jamming, COPA questioned why the goals of the exercise
cannot be achieved by performing it in a remote area of the country.
The response from DND was that it is most convenient and cost-effective
to conduct the exercise, which is an evaluation of several competing
hand-held GPSs for an upcoming purchase of 10,000 units.

COPA stated in the strongest possible terms that we are opposed to the
deliberate jamming of the GPS signal over such a large area and in a
location that will affect some of the busiest airspace in North
America. Even though the affected area is supposed to be an arc to the
north and east (a sparsely settled area), our understanding of GPS
signal propagation, including the weak power of the satellite signal,
leads us to believe that there is a significant potential for
interference* beyond the arc stated in the NOTAM. The reasons for the
exercise cannot possibly justify placing a large number of lives in
jeopardy. We illustrated the extent of the impact with some statistics.

About a year ago we surveyed our membership regarding their use of GPS.
We found that 68% had either a panel-mounted or handheld GPS and that
30% of those who did not have a GPS were planning to do so in the next
year. This survey was examined against the Transport Canada pilot
statistics in key areas and it was determined that the statistics from
our survey are representative of the pilot population as a whole. So,*a
conservative estimate of the percentage of Canadian pilots using GPS
now is 75%. The NOTAM states that jamming will occur as far as 250nm.
With our concerns that the jamming signal could go beyond its intended
arc to the north and east, this encompasses western Quebec as far as
Quebec City and Montreal, portions of the States of Vermont, New York
and Pennsylvania and most of southern Ontario including London,
Toronto, Kingston, Ottawa, North Bay and Sudbury.

The vast majority of pilots and aircraft in Ontario and Quebec are
located in the effected area. According to Transport Canada statistics,
of the 65,000 licences and permits in force in Canada, 38,000 are in
Quebec and Ontario. Given our survey results, there are 28,500 people
in the affected area in Canada who use GPS and could miss the NOTAM and
mistakenly follow a jammed GPS signal.*We could not estimate the number
of pilots affected south of the border, but*given the concentration of
pilots in the north east of the US, it*is easily tens times this
number.

The civil aircraft register web site was not available at the time that
this message was developed but we know from our past studies that the
number of aircraft closely parallels the distribution of pilots. So, of
the 29,000 aircraft in Canada, there are approximately 12,700 aircraft
equipped with a handheld or panel-mounted GPS in the affected area in
Canada alone.

Of course, the majority of the pilots mentioned above are not
instrument rated and we appreciate that GPS is supposed to be an
aid*rather than a primary means of navigation for VFR flight. However,
if there is any way that deliberate jamming can be prevented or at
least minimized, the safety of these users will not be degraded. The
more critical issue is the many*GPS instrument approaches in the
affected area.*We did not page through the approach publications but
there must be at least 100 GPS overlay or stand-alone approaches in
Ontario and Quebec plus many more than that south of the border.
When*approach aids are deliberately taken off the air for maintenance,
this is virtually always done only during periods of VFR conditions and
the NOTAMs state this provision. We saw no indication of this provision
in the above NOTAM and it was confirmed by DND that they will proceed
regardless of weather. This is a critical safety of flight issue.
While*we appreciate that pilots are supposed to check NOTAMs before
every flight, it is not acceptable to deliberately*produce a link in an
accident chain. Safeguards such as not performing the exercise during
IFR conditions would help prevent the chain from forming.

The critical question that should be considered by DND, Transport
Canada and NAV CANADA is why this exercise must be performed in the
most heavily populated area of Canada during a time of the year when
aviation activity is approaching its peak? We appreciate National
security requirements but it simply must be possible to achieve their
goals in a more remote area of Canada. DND disagrees, and stated that
very careful consideration was given to the safety issues. In fact,
Industry Canada, who manages the frequency spectrum, delayed the
exercise while it sought further data from DND.

COPA strongly urged the three agencies to meet as soon as possible with
a goal to stopping the exercise in the interest of flight safety. We
offered to cooperate with them in selecting a more suitable location
and also helping to get the word out to our members. We attempted to
delay, particularly because it is now too late now for us to reach our
members in our newspaper if the planned exercise proceeds because our
June newspaper just went to press. This leaves our web site and a
newsflash to COPA Flights as the only vehicle, plus of course hoping
that pilots diligently check all NOTAMs before they fly.

As of the date of this article, discussions with the three agencies did
not convince them to change their plans. So, please be aware of the
jamming that will occur on 9, 10, 11, 14 and 15 June from 1400Z to
1900Z. Do not conduct GPS approaches at the three airports and we
strongly recommend alternate means of navigation within 250nm of the
Killaloe VOR (YXI) on those days.

The issue of GPS signal jamming has been added to the agenda of the
next Air Navigation Services National Advisory Council meeting so that
solutions can be found for a safer way to perform these types of
exercises and notify affected people.