Fun With Parachute Mode
Last week, I took a ride over to Ft. Lauderdale to visit with Premier Aircraft. The company's been having good success selling Diamond aircraft (and Mooneys) and they have a premium upgrade package for the DA40 that includes a composite prop and a luxury interior.
I've always liked the DA40. It's got a terrific combination of decent speed, cockpit visibility and, especially, benign handling. And that's not just idle journalistic blather; the DA40 has an accident record to prove it.
The first time I flew the DA40, Jeff Owen was the demo pilot at Diamond and now he works at Premier, so we flew again last week. One thing he delights in demonstrating is what Diamond (and others) call parachute mode. Basically, you trim the airplane full nose up, idle the power and take your hands off the controls. The airplane will maintain a stable phugoid mode at a descent rate of between 600 and 1200 FPM at an indicated airspeed of 48 knots or so. In selling the DA40 against the Cirrus, Diamond has pointed out that in parachute mode, the Star might descend slower than the Cirrus does under its BRS parachute, albeit with more forward speed. (BRS says the Cirrus descent rate is between 900 and 1680 feet per minute.)
Would the DA40 be survivable if taken to the ground in parachute mode? Over rough ground, trees or an unfriendly urban environment, I'd be more than willing to take my chances in it, if a conventional engine-out landing wouldn't work. As these things go, 48 knots and 1000 FPM is fairly low energy.
Noodling this a little further, I dove into the accident records for the DA40 to see what's actually happening with the airplanes. The reality is there are hardly enough accidents to draw any conclusions. Nearly 1600 DA40s are flying and splitting Diamond's low and high fleet hours estimates, the 15 or so accidents it has had give it an overall accident rate of .8/100,000 hours, just a fraction of the GA average of 6.8. Its fatal rate is about .16, a mere eighth of the overall GA average.
The real eye opener is that in all those hours, there's not a single stall accident of any kind. I don't think many, if any, other airplanes can make this claim. Given the number of high-profile stall accidents we've seen recently (Colgan and AF 447), this record is remarkable, in my view. While it may be true the DA40 is used as a trainer and its high-aspect, low wing loading make it less susceptible to stalls, it's also true things like this haven't kept pilots from unintentional stalls anyway. But evidently not in the DA40.
By the way, parachute mode works in other airplanes, too. But not necessarily as well, because the phugoid is less damped and the down-cycle airspeed builds to yield a higher descent rate. Next time you're out flying, try it. It could be a revealing exercise that might save your life.












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