Page 28 - mmopaMJ21

lowered the nose to maintain altitude. Conversely, speed would decrease in the downdraft as the nose pitches up to maintain altitude. In the next four minutes, the ground speed begins a steady decline with a relatively small change in altitude. At 28 minutes into the flight, the ground speed drops from 110 kts to 55 kts in a 1 minute period followed by a small ground speed oscillation and then flight termination.
Mountain wave is not always characterized by turbulence. Modern autopilots can correct for this phenomenon such that you might not even notice speed changes of +/- 20-30 kts unless you’re actively watching the airspeed indicator. The tracklog from a different flight shows a Mirage in the flight levels near Pueblo and an impressive mountain wave experience. As the airspeed cratered, the pilot disconnected the autopilot and looked for a place to divert. Fortunately, the event subsided, and his airspeed returned.
The wind was not the only concern. The reported weather at Tehachapi (4,001 feet MSL) was 31019G26KT 10SM BKN012 BKN017 OVC025 05/04. Icing would be possible at around 6,500 feet MSL and up. Under these conditions, a non-instrument-rated pilot would likely be in/ out of the clouds and experiencing some icing. The METAR from Mojave, about 16 nm east of the accident site was 30033G47 10SM CLR.
Synthetic vision, deicing equipment, and a good autopilot may have emboldened the pilot to continue and distracted him from the airspeed fluctuations.
The flight started/terminated on Friday afternoon. The aircraft tail was spotted sticking out of the snow. The wind and weather conditions were such that Search and Rescue personnel were unable to reach the site until Sunday.
E: External Pressure
We have to evaluate the reasons for any flight and consider the decision process. If you’ve taken an Airman Knowledge Test in the past decade, you’ll be familiar with the hazardous attitudes; invulnerable, impulsive, macho, anti-authority, and resignation. Every person (not just pilots) has them and one is usually dominant in one’s personality. When you evaluate a situation, these attitudes kick in and bias your decision and support your “excuses” to accept or not accept risk. Sure,
the end of the week/business day and we don’t know what time he started that day. Had it been a tough week? All these distractions can adversely affect performance and decision-making.
He was familiar with the route and may have flown it under similar circumstances and everything had worked out. As everyone knows; everything is alright, until it’s not.
In our society, we reward accomplishments or “getting it done.” We celebrate sporting competitions, business successes, and so on. We don’t acknowledge good judgment, especially when it impedes accomplishments. Maybe we should.
Remember: There’s nowhere you need to be or nothing you need to do that’s more important than safety!
Stay safe.
it’s a risky flight but it’s only an hour and a half and I have
to get there tonight. The FAA won’t know that I flew in the clouds. I’m a great pilot and I’m quite capable of handling the situation, especially with my equipment. Accidents happen to the other guy. And so on. Had he been carrying passengers; his decision process might have been, would hopefully have been different.
We don’t know the reason for the trip. It was the day before Valentine’s day. It was a weekend. Mammoth Lakes is certainly a much nicer place than LA (no offense Angelenos). He could probably get there faster than driving cross-town to LA. We also don’t know if fatigue was a factor. It was
Dave McVinnie is a 25-year Master Flight Instructor, a 2020 MMOPA Master Aviator, an FAAST Representative and a Des- ignated Pilot Examiner with over 12,000 hours and 35-years of instructional experience. The FAA selected him as CFI of the Year in 1995, 2009 & 2014. Dave currently serves on the MMOPA Safety Committee and has specialized in the PA-46 for the past 20-years. McVinnie Aviation offers insurance ac- cepted initial and recurrent training, including initial instrument training. For more info, go to McVinnieAviation.com
28 MMOPA MAGAZINE MAY / JUNE 2021