CHIEF WARRANT OFFICER 4 ROGER WILSON
U.S. Army Flight Training Detachment
Silverbell Army Heliport
Marana, Arizona
The following incident happened a few years ago while I was an AH-64A instructor pilot at the Western Army National Guard Aviation Training Site at Silverbell Army Heliport in Marana, Arizona. It demonstrated to me that when things happen, some of them go the way you want while others do not.
It was the summer monsoon season, and I was an instructor in the night phase of training using forward-looking infrared (FLIR). The daily briefing was conducted, and the weather forecast called for thunderstorms in the vicinity of the mountains with a wind advisory up to 20 knots. A weather cell in the area was 30 miles to the east and moving in our direction. It was a pretty normal night with a high overcast at 7,000 feet.
No anomalies were noted during the aircraft preflight, so I conducted a run-up and takeoff with my first-period student. It was his first night in the front seat flying with the target acquisition and designator sight (TADS). The syllabus called for him to practice base tasks at the stagefield. We flew the corridor to the stagefield, and our aircraft was the first to arrive and begin training.
The Picacho Stagefield tower advised us that winds were variable at 5 knots. After our second approach and landing, my student pilot told me his FLIR picture disappeared and the caution light on the TADS was lit. I took the controls, exited traffic on the downwind and proceeded to return to base. En route at five miles out, I contacted base operations and was told there was a weather recall. Airfield visibility was reduced to one-quarter mile with dust and winds over 50 knots.
Another AH-64 on the runway preparing to take off announced visibility was zero. With my unaided eye, I saw the lights for the airfield disappear, but aided with the FLIR, I could see the wall of dust, or haboob, approaching. We decided to turn back and return to Picacho Stagefield, where the weather was fine. I began to execute a 180-degree turn while my student reversed our GPS route. We were flying at a speed of 110 knots at 700 feet altitude. Then it hit us.
The haboob overtook us, and I announced instrument meteorological conditions (IMC). I was immediately in the worst turbulence and downdraft I ever experienced. My front-seater asked what he could do to help. I told him to call out airspeed and altitude while I adjusted pitch attitude to maximum rate of climb and pulled in max torque available. Our rate of descent was incredible and I could not stop it. I bled the rotor to 99% and my radar altitude tape appeared in my symbology, letting me know we were below 200 feet altitude.
At 110 feet above ground level (AGL), we encountered the updraft of the haboob and within seconds were above the dust storm at 2,000 feet AGL. We recovered to Picacho Stagefield and landed just as the winds hit. We waited 30 minutes for the winds to die down before we could perform shutdown procedures.
I had taken my instrument Annual Proficiency and Readiness Test just the day before and practiced inadvertent instrument meteorological conditions (IIMC) flying. This, no doubt, allowed me to transition to the instruments quickly and maintain aircraft control. That storm resulted in a 300-vehicle pileup and three fatalities on Interstate 10.
When we reviewed what happened to us, we realized there were lessons to be learned from our experience.
Things that went wrong
Base operations issued a recall after conditions were IMC at the airfield. This has been corrected by a change to our standard operating procedures. The weather unit supporting us did not issue a weather warning, so the criteria for weather warnings, watches and advisories were changed to keep base operations informed earlier of approaching storms.
Things that went right
Our crew coordination was good, and my front-seater did an awesome job providing me with data callouts, working the radios and communicating with the tower. I felt my recent evaluation while flying under instrument conditions is what allowed me to commit to instruments as quickly as I did. The message here — hood minimums may save your life someday.