Date: 201505
Local time of day: 1801-2400
Location: 89TA.Airport, TX
Flight conditions: VMC
Weather elements / visibility: 10
Light: Daylight
Aircraft: Small Aircraft; Low Wing; 1 Eng; Fixed Gear
Operator: Personal
Operating under: Part 91
Flight plan: None
Mission: Other Glider Tow
Flight phase: Climb
Airspace: Class E ZHU
ATC / advisory: UNICOM CTAF
Second aircraft: Commercial Fixed Wing
Reporter organization: Personal
Reporter function: Single Pilot
Reporter qualification: Flight Crew Commercial
Human factors: Troubleshooting; Distraction; Situational Awareness; Communication Breakdown
Anomaly: Conflict NMAC
Detector: Person Flight Crew
When detected: In-flight
Result: Flight Crew Took Evasive Action
Contributing factors: Human Factors; Procedure
Primary problem: Procedure

Narrative: I departed ZZZ at the controls of Aircraft X with Aircraft Y in tow.  The glider pilot requested a 3;000 feet AGL tow and desired to 'box the wake' after reaching 2;000 feet AGL.  After reaching 2;000 feet AGL (2;400 feet MSL); I noticed conflicting traffic during my visual scan of the area.  The conflicting traffic was Aircraft Z.  When I first noticed the traffic; it was at my 10 o'clock position and approximately 1-2 NM distance from my aircraft.  The aircraft was heading westward in straight and level flight; and I was heading southward and climbing approximately 300-400 fpm with Aircraft Y in tow. I determined that my aircraft and Aircraft Z were converging to a near-collision.  The Aircraft Y pilot requested via radio to begin 'boxing the wake;' and I replied with distance and direction information about the conflicting traffic and instructed the Aircraft Y pilot to postpone the maneuver.  The Aircraft Y pilot replied that he did not have visual contact with Aircraft Z.  I decided to continue southward without releasing Aircraft Y and performing an evasive maneuver because the Aircraft Y pilot did not have visual contact with Aircraft Z.  I was concerned that; after releasing from the Aircraft Y the Aircraft Y pilot would maneuver in conflict with Aircraft Z. I did not level off because doing so abruptly could result in the glider overshooting and 'kiting' above my aircraft; leading to controllability issues.  Additionally; a turn to the left or right would further place my aircraft and Aircraft Y in a collision course with Aircraft Z.  I deduced that; barring any change in flight path by either my aircraft or Aircraft Z; Aircraft Z would pass behind me and at the same altitude. Aircraft Z ultimately passed behind Aircraft Y in tow by approximately 100-150 yards and at an altitude approximately 100-200 feet below the altitude of Aircraft Y in tow.  I continued southward and Aircraft Z continued westward.  At no point during the encounter did Aircraft Z pilot appear to have my aircraft or Aircraft Y in tow in sight.  The Aircraft Z pilot did not make an evasive maneuver and did not yield to my aircraft or Aircraft Y in tow.  The Aircraft Z pilot did not attempt any radio communications during the encounter.  I received the impression that the Aircraft Z pilot was completely unaware of the near-miss; despite the very small margin and my aircraft appearing almost directly in front of the Aircraft Z pilot's view. 14 CFR Part 91.113(d) states that an aircraft towing or refueling another aircraft has right-of-way over all other engine-driven aircraft.  This is undoubtedly due to the fact that aircraft engaged in towing are far less maneuverable than other aircraft.  I believe that this near-miss incident demonstrates the large difference in maneuverability between aircraft towing other aircraft compared to other engine-driven aircraft.  I found myself significantly limited in my options to safely avoid Aircraft Z.  Despite having the right-of-way; I was prepared to take evasive action.  'See and avoid' is a responsibility of every pilot; despite right-of-way rules.  I chose not to alter my flight path because I believe that doing so would increase the risk of collision.   ZZZ is marked with a symbol depicting its status as an area of glider operations on the VFR sectional chart and Terminal Aeronautical Chart.  Adjacent to this symbol is a box that reads 'Caution Intensive Glider Activity' and provides the radio frequency used for glider operations.  I have noticed that many powered aircraft transition through the area without communicating with glider and tow plane pilots.  The high volume of glider traffic; as well as the difficulty of visually identifying gliders; makes the area potentially dangerous for transitioning powered aircraft.  I urge pilots transitioning through glider operations areas to plan accordingly; communicate with local traffic; and exercise extreme caution.




Synopsis: Pilot of an aircraft that is towing another aircraft reports of a near miss with a third aircraft. Pilot speculates that the third aircraft never saw the two aircraft formation.