Analysis of Luke AFB Hazardous Air Traffic Reports (HATRs)

2000-2003

Introduction

This report is based on data from thirty-four Hazardous Air Traffic Reports filed between February 2000 and September 2003. The parameters considered were year, month, date, day of the week, time of day, altitude, radial and DME from the Luke TACAN (located on the airfield), phase of flight, aircraft type, whether or not ATC gave the Luke assigned pilot a verbal traffic “point-out”, and whether or not ATC had radio contact with the conflicting traffic. Trends regarding these individual parameters are presented in the individual sections and in the conclusion section.

Year Trends

HATRs have shown a clearly increasing trend on an annual basis. HATRs have increased by an average of two events per year.

The chart above shows a clearly increasing trend. The 2002 year does show a decrease, but this can be attributed to a period of inadequate data collection rather than an actual decrease in near-miss events. 2003 is likely to have an actual HATR count that is much higher due to the months still remaining in the calendar year.

Monthly Trends

The following chart shows the number of HATRs occurring during each month.

While monthly events appear to be relatively constant, the data indicate the five months (May-September), with the exception of July, have a greater number of HATRs.

Date Trends

Analysis of date of the month (i.e. 3 Nov vs. 10 Nov) shows no trend information relating to date of the month for the HATR events.

Day of the Week Trends

The day of the week presents no compelling trend information. As expected, Friday has a lower count due to a decreased Luke AFB flying schedule.

Time of Day Trends

Time of day data presented a surprising trend that can be seen in the following chart.

This chart shows a dramatic trend with 50% (17) of all Luke HATRs occurred during the time from 1500-1700. With Luke AFB flights scheduled between approximately 0730 and 2300 local each day, one might expect a constant distribution of HATRs during the day with a decrease at night due to less VFR traffic and fewer Luke flights. This is clearly not the case. To ensure that the trend indicated by the above chart was not simply a spike during a particular year, the time window of 1500-1700 was analyzed for each year. The respective proportion by year for 2000-2003 are 100%, 60%, 72%, and 33%. Every year, the 1500-1700 time window accounted for the highest number of HATRs.

Altitude Trends

Altitude data indicate a clear but expected trend in which HATRs are more prevalent at altitudes where general aviation traffic operates. The following chart depicts mean sea level altitude concentrations:

The areas between 3000’ and 5000’ account for 62% of Luke HATRs.

Radial Bearing from Luke TACAN Trends

Radial bearing data from Luke TACAN follows the expected trend of higher concentrations on the arrival and departure corridors of the extended runway centerline.

This chart does indicate that most HATRs occur north of Luke AFB.

DME Trends

DME data indicates that a much greater number of HATRs occur near the base:

The greatest concentration (35%) occurs at 10 to 15 miles from the base. The four HATRs occurring at greater than 40 miles occurred during MOA or low-level operations.

Phase of Flight Trends

Of the 34 reports, 55% (19) occurred during the ILS IFR approach phase of flight. Only 6% (2) occurred during VFR recovery. Furthermore, the ILS recovery accounts for 90% of recovery related HATRs, although only about 25% of recoveries are IFR recoveries. This is not a recent trend. With the same year-to-year consistency, IFR recoveries account for the greatest number of HATRs every year.

Aircraft Type Trends

Aircraft type data shows that Luke’s near-miss events are occurring to an overwhelming degree (80%) with powered general aviation aircraft. The following chart shows the concentrations:

Important conclusions are that glider events represent less than 10% of HATRs and that there are zero HATRs with airline traffic. Furthermore, the F-16 vs. F-16 HATR rate of 12% (four over four years) shows that pilots and controllers are able to proficiently deconflict Luke based aircraft.

ATC Point-Out Trends

A surprising trend is a nearly even split of HATRs occurring after ATC point-outs versus no ATC point-out. In fact 53% of HATRs occurred after ATC made a traffic point out versus the 47% with no point out.

ATC Radio Contact Trends

In contrast to ATC point-outs, radio contact with conflicting aircraft does reduce the likelihood of a HATR event. Only 20% of HATRs occurred when ATC had radio contact with the conflicting aircraft. This dictates that efforts to encourage non-Luke aircraft to contact Luke ATC must be continued. Current efforts include public education efforts by Luke personnel and directions that recommend contact with Luke ATC printed on civilian aeronautical charts.

Conclusion

Analysis of the Luke AFB HATRs filed over the last four years provides meaningful trend information that can be used to target the highest threat areas. Analysis of the data led to numerous conclusions. HATRs have increased by an average of two events per year. While monthly events appear to be relatively constant, the data indicate the five months (May-September), with the exception of July, have a greater number of HATRs. Radial bearing data from Luke TACAN follows the expected trend of higher concentrations on the arrival and departure corridors of the extended runway centerline.

The greatest concentration of HATRs occurs between 10 to 15 miles from the base. Aircraft type data shows that Luke’s near-miss events are occurring to an overwhelming degree (80%) with powered general aviation aircraft. 53% of HATRs occurred after ATC made a traffic point out versus the 47% with no point out. In contrast to ATC point-outs, radio contact with conflicting aircraft does reduce the likelihood of a HATR event. Finally, the most significant trends concern phase of flight and time of day. Of the 34 reports, 55% (19) occurred during the ILS IFR approach phase of flight. Only 6% (2) occurred during VFR recovery. Furthermore, the ILS recovery accounts for 90% of recovery related HATRs, although only about 25% of recoveries are IFR recoveries. This is not a recent trend. With the same year-to-year consistency, IFR recoveries account for the greatest number of HATRs every year. Additionally, every year, the 1500-1700 time window accounted for the highest number of HATRs