Step Down Disaster

I crashed and died the other day … and took my CFII to the grave with me. At the controls of an AST-300 simulator, we lifted off runway 29 at virtual-Akron, Colorado. I knew I’d like flying a DME Arc…

The plan: Fly a standard-rate right climbing turn to intercept the 50-degree radial ‘FROM’ the Akron (AKO) VOR and go out 10-miles … then, turn 90-degrees to a 140 heading and fly a 10-mile DME Arc. (Turn 10 degrees right on the Heading Indicator (HI) and Twist 10 degrees on the VOR — Turn 10, Twist 10.) At the 110 radial, turn inbound 290 degrees on-course ‘TO’ the VOR. (No Procedure Turn — NoPT.) From there, step down fixes: 6,000 to 5,300, cross the VOR, drop down to the Minimum Descent Altitude ‘MDA 5120,’ fly to the Missed Approach Point (MAP) and land at the virtual-Akron Airport (KAKO) … or go missed.

I think I flew the Arc pretty well, maybe just O.K., since I’m new at this. I turned a little late to get on 290 degrees ‘TO,’ S-turned a bit getting on the inbound course. Pulled and set the power to a Manifold Pressure of 14.00 … tried to capture a 500 fpm descent on the VSI and 100 knots on the airspeed…got to 5300 feet and expected to cross the VOR. At station passage, I followed the approach plate and dropped down to 4681, call it 4700, to the Missed Approach Point before looking for the runway. My instructor put the sim on hold. ‘Look up,’ he said. On the screen, I saw green grass and a runway at eye level. We were dead — or about to be, anyway. Accident investigators call this ‘Controlled Flight Into Terrain’ (CFIT).

The way I saw it, I crossed the VOR, glanced at the Approach Plate, saw 4681 feet on the Profile View and watched the altimeter unwind to 4700 for an ounce of safety. But this was the altitude for the Touch Down Zone (TDZE)–not the 5120 Minimum Descent Altitude (MDA).

I had picked the wrong number from the Profile View and flew us into the ground.

Aside from the obvious, my instructor pointed out a fundamental mistake in my process. ‘You didn’t do the 5-T’s (Turn, Time, Twist, Throttle, Talk) when you crossed the final fix at the VOR,’ he said. For me, the key ‘T’ out of the five was Time. At 100 knots IAS, a 570 fpm descent should take one minute and one second. I flew the descent on and on … well beyond one minute. I did not start the clock at the VOR final fix and time the descent to the Missed Approach Point, with the following results: Aack! Smash! Splat … ‘he died doing what he loves.’ Of course, that last part is bunk. I do not like making silly mistakes on approach and getting myself — and my passenger — killed. I don’t know anyone who does.


  1. The Touch Down Zone elevation is listed just above the Minimum Descent Altitude on the Approach Plate.
  2. If you mistake the two numbers, you can end up dead.
  3. DO THE 5-T’s, or miss your next tee-off time.