Balloon
Flight Crew Commercial; Flight Crew Multiengine; Flight Crew Instrument
Flight Crew Last 90 Days 8; Flight Crew Total 2396
Communication Breakdown; Training / Qualification; Distraction; Situational Awareness
Aircraft Equipment Problem Less Severe; Deviation - Altitude Overshoot; Deviation / Discrepancy - Procedural FAR; Deviation / Discrepancy - Procedural Published Material / Policy; Inflight Event / Encounter Weather / Turbulence
Air Traffic Control Provided Assistance; Flight Crew Overcame Equipment Problem; Flight Crew Returned To Clearance
Environment - Non Weather Related; Aircraft; Human Factors; Weather
I was PIC; sole occupant of an Experimental hot-air balloon making a climb to 21;000 to exceed the minimum requirements for [a competition] altitude task. I was under a waiver from [the FAA] and an LOA (Letter of Agreement) from ZZZ Center. The maximum altitude in the LOA and Waiver was 21;000 feet. High altitude hot-air ballooning is done very rarely so there is no way to practice for a flight like mine. I researched previous record attempts and spoke to others who have flown there but sometimes things happen that you are not expecting. This flight was no exception. I was in the high teens approaching 20;000 and started to have intermittent partial burner flameouts; I am sure due to oxygen starvation due to thin air and cold temps. The procedure then is to slowly throttle in the auxiliary burner to act as a pilot light and maintain climb. The auxiliary burner is a 'floppy and weak' flame but it works. The problem that arose was mild wind shear at altitude was blowing the auxiliary burner flame away from the mouth of the balloon so I had to add more throttle to keep heat in the balloon and prevent flameouts. This created a tremendous amount more noise in the basket and my climb rate increased. I was unable to hear Center on my radio because of the noise and the fact I had a speaker not a headset. The provisions in the LOA worked as they called my ground crew via cell phone to be kept updated. Flying on the auxiliary burner is not precise especially at high altitudes. My goal was to fly the aircraft first and communicate later. I did have a discreet Squawk Code so Center knew where I was and whether I was climbing or descending. It took a little while to get the balloon under control and start a slow controlled descent. I alerted Center via 3 hits on the Ident button on my transponder per the LOA. Unfortunately I exceeded the max altitude of the LOA (22;200 feet) during this time. Once back at lower altitudes all systems went back to normal and I reestablished contact with ATC. I landed in the first field available. The landowners were very accommodating and helpful until my ground crew could get to me. I called Indy Center per the LOA as soon as we had cell coverage and went over the flight with them. They seemed to understand what happened and seemed enthusiastic about working a balloon. They said vectoring traffic around me was not difficult as my ground speed was so slow. Possible solutions if going higher I would modify the burner with an oxidizer for the pilot lights to prevent flameouts; especially over 25K. Add a 360 skirt to the mouth of the balloon to protect the flame from wind shear. Wear a noise attenuating headset with a push to talk button.
Hot air balloon pilot reported exceeding altitude specified in LOA with ARTCC.