By:  Jack  Serig, Sr.

    Ft. Riley, Kansas was the home of the BIG RED ONE (1st Infantry Division) when I was assigned there from Germany in late 1959.

    The first year at Riley was a ground duty assignment with an infantry training company, which was a career necessity and  one that we thoroughly enjoyed.  Hungry to get back into a flying assignment, my request for transfer to the 18th Aviation Company (Otter)* was approved.
Upon reporting, the commanding  officer advised of my pending assignment as a Flight Platoon Leader.  A few weeks later a summons to his office revealed a change of plans.  I was to replace his departing, school-trained aircraft maintenance officer, i.e., Service Platoon Commander.  Protesting that I was not maintenance qualified was to no avail.

    While settling in and getting acquainted with the platoon members, and in discussions with unit pilots and crews, a serious problem was brought to my attention for resolution.  In the previous 18 months a total of 12 unit  Otters had either been involved in emergency forced landings, or precautionary landings, due to total or partial loss of engine power.

    Our platoon team, consisting of Platoon Sergeant Snyder, Flight Line Chief Holly, Technical Inspector Helbing, and myself,  were determined to solve the problem.  We began by in-depth reviews of aircrafts’ maintenance histories, precautionary and forced landings’ reports and more discussions with crewmembers involved in the mishaps.  Each of the incidents was thoroughly examined based on available documentation and recollections by crews.

    Incidentally, our Otter unit was blessed with a great group of remarkably experienced aviators, many with Korean and World War II service.  Those at the controls at the time of the 12 potential mishaps had saved all 12 without damage, destruction, injuries or loss of life.  Some help was provided by the lay of the terrain in the general area we flew in, the relatively flat parts of Kansas, Oklahoma and Texas.  Our guys had been setting planes down in corn and wheat fields and off the ends of runways, when engine power was reduced or completely lost.

    As a result of extensive, and intensive, priority research our team developed evidence of three separate, potentially dangerous problems.  First, in some power losses, records revealed cracks between the spark plug holes in the engines’ cylinders.  Second push-pull rods were bending beyond tolerances or ball ends were failing.  And third, cylinders were not factory stamped with the number of hours they had accumulated at their previous overhauls.  Consequently, total cylinder hours could not be determined and cylinders, aged beyond their design limits, were failing.

    It was decided between our unit’s staff and the staff of our third echelon maintenance support company, the 339th, with the concurrence of the battalion commander and staff, that we would tear down three Otter engines, those with the most hours since rebuild.  The 339th crews, supported by the Otter crew chiefs, began day and night crew shifts to expedite the process of determining the existing condition of our fleet of engines, nineteen in all.  Within several weeks we had indisputable evidence that our research findings were supported by the engine teardown findings learned in the 339th shop.  An average of 33% of cylinders and/or push-pull rods failed to meet the criteria spelled out in the technical manual.  This average remained constant for all engines upon teardown inspections.

    During the above events a new commanding officer reported to the 18th, Bob Felix.  In his Otter solo checkout, in the pattern, shooting touch-and-go’s, he experienced engine failure resulting in another successful dead stick landing, NUMBER 13.  When he walked through my office door, the first time we met, the expression on his face reminded me of the proverbial “bull in the china shop.”  He let loose with a predictable gnashing and lashing wanting to know what was wrong with our maintenance.  Fortunately, the information was opened up, spreadsheet fashion, on my desk.  He calmed down when we advised him of our findings to date and our efforts to correct the problems.  He became immediately supportive and remained so throughout our association.

    As a result of our findings I recommended that all our Otters be grounded.  This was approved by the company and battalion commanders with the knowledge of the 1st Infantry Division Commanding General.  A recommendation for worldwide grounding of all Otters in the Army’s inventory was also approved and sent to appropriate commands.  Remember, you ‘ol Otter crew members---the year was 1961!  However, this worldwide grounding recommendation fueled a feud between our command and the “powers to be” in the Aviation Material Command, the DeHavilland people and the Pratt and Whitney experts.  They didn’t believe us, initially.  But we were proved right in our assessment after many heated meetings when our substantiating evidence was presented.

    In short order, between the initiatives of the 339th crews and the backup support from the Army Depot at Eagle Mountain Lake, Texas, all of our engines were rebuilt within a few months.  In effect, we had the equivalent of new Otter engines.

    Our unit commander approved another recommendation to perform night maintenance, once  our aircraft were returned from engine overhaul.  By performing the majority of maintenance at night our aircraft availability and daytime flying hours, we believed, should be significantly increased.  That’s exactly what happened.

    We were a Strategic Army Command (STRAC) unit, ready to be deployed anywhere in the world on short notice.  When the Pentagon staff saw our aircraft availability rate had increased well above that of all other existing Otter units, we had a visitor, Major Ken Mertel.  He was apparently convinced with what he saw.  We were not fudging!  Shortly after he returned to the Pentagon we were ordered to Southeast Asia, country unspecified.  It was December 23rd, 1961.

Jan 1962, enroute to RVN USNC Core     In early January 1962, we loaded with our aircraft at the Navy docks at  Oakland, California on the USNS Core, a World War II vintage “jeep” carrier, accompanied by our 339th support maintenance element.

Jack, Service Platoon Commander, Nha Trang, 1962     All 18th Otter crew members were thankful for the discoveries which led to our rebuilt engines, especially when they saw the extensive mountainous and jungled terrain we would be flying over and the monsoon rains we would be flying in throughout South Vietnam.  Our unit, having experienced 13 forced and precautionary landings in the previous 18 months, had only 2 during our twelve-month tour, with no injuries and no damage to aircraft.  

Aerial view of Hue, mid-1962    

*Otter:  An 11-place single engine airplane purchased off-the-shelf from DeHavilland of Canada for STOL (short takeoff/landing) capabilities.  Powered by a 9-cylinder, 1350 hp Pratt & Whitney engine.

This article was published in the LOGBOOK, a tri-annual publication of the Army Otter-Caribou Association, in the November, 1991 edition.