Diamond DA40: Airline Pilot Trainer (Part II)

Takeoff and Climb
The DA40’s low stance and tremendous visibility make it seem like you’re sitting right on the runway when you line up for takeoff.Advance the power and it’s difficult at first to maintain centerline—left-turning tendencies and lack of nosewheel steering meant that even with a three-knot left crosswind component I needed partial braking on the right pedal early in the takeoff roll.The demo pilot told me he’s landed with as much as 30 knots crosswind, but that would’ve been at idle power and a lot more air flowing over the Diamond’s rudder.The DA40 will definitely teach (and require) good rudder technique on takeoff, and may help revive the lost art of using adverse yaw (with deflection of ailerons) to aid in runway directional control.

The Diamond lifts quickly and smoothly airborne.Diamond does not publish a Vx speed for the DA40—problematic in training for and passing the Private Pilot and Commercial checkrides.Vy comes at about a +10 degree attitude (referencing the attitude indicator) above the horizon after flap retraction. The DA40 is a great airplane in which to teach “integrated” (visual and instrument references combined) flying techniques.In fact, since the windscreen and nose slope down so steeply, there’s almost no outside structure with which to gain a “sight picture.”You have to crosscheck the flight instruments to achieve any level of precision.

Give it the necessary right rudder in climb (Diamond has said they may incorporate the DA42 twin’s rudder trim system into future DA40s) and the airplane climbs smartly.Cruise climb at 100 knots indicated (about seven degrees nose up) and forward visibility is very good with little loss of climb rate.Cabin air vents provide good flow, but are noisy (also fixed somewhat in later airplanes).The tight cowling keeps the engine cool.

Air Work
Leveling off requires preplanning; the DA40 is a slick airframe with a good thrust-to-weight ratio, meaning it’ll want to keep climbing.Level-off is best initiated at 500 to 1000 feet early, lowering the nose to about five degrees up (netting around 500 feet per minute climb) and trimming off the pressure as the airplane accelerates. Another nudge forward on the stick starting about 50 feet before altitude, accompanied by more nose-down trim, allows a smooth transition to level flight.It’s a good trainer to teach pilots to stay ahead of the airplane.

About that stick—once the standard in aircraft control, the stick fell from favor from most civil airplanes before the Second World War.Strangely, though, my experience, and that of everyone I’ve ever checked out in stick-controlled airplanes, is that the transition to the stick is completely effortless.There is only one set of engine controls, in the center console, so the right-seat pilot flies left-handed, and the left with his or her right hand.Still, it takes little effort—except if you have to switch hands to take notes or copy a clearance.

Crosscheck the attitude (level to even a degree nose down), let the Diamond accelerate, then set cruise power.It’ll get up to 145 knots true airspeed at 11 gallons per hour fuel burn, fast for modern cross-country training yet economical for the flight school.Control forces are light, but not too light—I was amazed that the airplane trims out rock-steady, unlike many composite ships that stem from the experimental world.The DA40 is a rudder airplane belying its sailplane heritage.There’s a lot of adverse yaw in turns; it takes a lot of left rudder to maintain coordination in descent, like a Citabria.The DA40 will certainly teach rudder control.

Slowing below the 108 knot Va speed for maneuvers means about 15 inches of manifold pressure at 2450 rpm.Steep turns require feeding power back in after rolling into the turn; I found the steady-state, 108-knot steep turn to ultimately require around 19 inches of manifold pressure and a five degree nose-up attitude (again, there’s not much outside to reference to the horizon).Don’t forget to pull the power back and ease the nose down during roll-out to avoid gaining altitude or speed.

Stalls are very straightforward.There is no stall break, even with power on–the nose stays high and the vertical speed dumps to about 1000 fpm.  Keep the stick back and it’ll stay in this mush.  Any aileron input DRAMATICALLY aggravates the stall and invites a spin.I later wrote the word “critical” on my kneeboard next to my note to check aileron effect during a stall on my demonstration flight.The rudder is extremely effective in the stall for holding heading and wings level.  Recovery is easy by simple reduction of angle of attack while holding against roll and yaw with positive rudder inputs.

Approach and Landing
A solid undercast filled beneath our wings and we picked up an IFR clearance with vectors to the ILS.As we stepped down in our descent I experimented with some power settings.The Diamonstar is very slick, good for training jet-style energy management techniques and the need for descent and approach planning.It simply does not want to go down and slow down at the same time.

The DA40 started to feel “squirrelly” at the traditional 90-knot approach speed.My technique is to fly the approach trimmed for the climb out speed to make missed approaches a nonevent anyway, and the Diamondstar feels much more solid at 100 knots.Using the “takeoff” flap setting for drag and a lower nose attitude (all the better to find runways in the murk), it took about 17 inches of manifold pressure and 2500 rpm (climb setting) to hold 100 knots in level flight.Trim is at the takeoff setting, too, when pressures are relieved.A glideslope-hugging 550 fpm descent, still trimmed for 100 knots, results when you pull the power back to 12.5 inches.

Flying a nonprecision approach?From the level flight, 100 knot configuration reduce manifold pressure to nine inches and you’ll get 800-1000 fpm descent, still trimmed.Bring power back up to 17 inches for intermediate level-offs and the final flight at Minimum Descent Altitude.From either a precision or nonprecision approach, all it takes is full throttle, nose up to seven to 10 degrees up, and retract flaps to climb out from the missed approach point, with little to no change in trim.The DA40 has a very stable and extremely low workload.

Breaking out a few hundred feet above minimums, I had time to pull the power back and transition to a visual landing.Trim change is not great (anticipate the nose-down effect of extending full flaps) in the flare.Full flaps are recommended and available below 91 knots.Airspeed control is vital as the slick airplane will float if just a few knots fast.Use all the crosswind correction you need without worry; the free-castoring nosewheel is blown into the centered position until it touches down.Slow to a slow walk before turning off the runway, though; you’ll need to use brake to caster the nosewheel to turn, and if you’re going too fast you’ll wear the brakes excessively and risk putting a damaging sideload on the nose strut after the wheel turns.Clear the active, process your after-landing checklist, snap the canopy up to the taxi position for some cool air, and realize just how much you’re smiling for having flown the DA40.

Pros and Cons
I told the Riddle folks they made a good choice for an ab initio airline pilot trainer.Like any choice, there are pros and cons (and some points that could go wither way) about the DA40:

Pros:

  • Exciting, next-generation airplane
  • Easy to fly
  • Visibility, comfort and headroom are excellent in front and rear seats
  • Teaches good rudder technique
  • Teaches preplanning and energy management techniques
  • Good platform for teaching integrated flight techniques
  • Master caution and fault annunicator panel anticipates jet-style equipment
  • Electric instruments make more realistic partial panel transitions possible
  • Newest models offer airline-like PFD/MFD displays
  • The DA40 I flew has 874 pounds useful load in an IFR configuration (cloth seats).  40 gallons fuel (full) leaves 634 pounds for crew (plenty for student, instructor and observer/pilot not flying).Cons:
  • It’s HOT under the Plexiglass® with little ground ventilation.
  • Front and rear left seat cushions will take a lot of abuse from entry and exit
  • Preflight inspection is limited by T-tail and closely-fit cowling and wheel pants.
  • Lack of nosewheel steering makes directional control difficult early in the takeoff roll.
  • Differential-braking steering means more frequent brake pad replacement.
  • Very little room for charts, flight bags, or instructional equipment.
  • No published Vx speed or guidance in the POH.
  • The DA40 is sorely in need of rudder trim.
  • Standard fuel allows for 3 hours 15 minutes flight (leaned for cruise) with 45 minutes’ reserve. Two 1.5 hour sessions back-to-back will not require refueling when students swap seats, but longer missions (typical in IFR training) will necessitate refueling between lessons.
  • Towbar storage location
  • Still requires school to operate another aircraft (retractable gear and bigger engine) to train to Commercial certificate, high performance and/or complex aircraft endorsements.
  • Although Diamond’s two-seat airplanes have held up well in instructional roles, the jury’s still out on whether composite airplanes can handle the stress of long-term instructional use.
  • Even minor dings may require extensive composite repairs at the Diamond factory, as the general aviation industry isn’t trained or equipped to make field repairs to composites.Good or bad (depending on your point of view):
  • There’s no stall break, just a rapid-descent mush.
  • Ailerons must be kept perfectly level in stall recoveries.Overall assessment? I think that Diamond DA40 makes a superb ab initio trainer for prospective career pilots.Instructors will have to teach integrated flight techniques and stress rudder coordination to a much greater extent than other airplanes demand—and will likely turn out better pilots in the process.Higher times before solo and total time to complete the Private Pilot certificate are likely given the demands of the DA40, more so if the airplane is equipped with glass-cockpit PFDs and MFDs that take additional time to master (computer-based training would be a good complement in such cases).The corollary is that pilots trained with the DA40 and PFD/MFDs will find it far easier to transition to more capable airplanes later.I suggest weekly mechanic’s inspections to check hard-to-see items like engine compartments, tires and brakes and the horizontal tail; and inside storage during cold-weather precipitation or frost and when birds are nesting in the area.Preflight, weekly and scheduled FAA inspections should include close inspections of the airframe for any signs of stress-related cracks or wear.