From: dst+@cs.cmu.edu (Dave Touretzky)
Newsgroups: rec.aviation
Subject: slandering twins
Date: 11 Sep 92 01:28:01 GMT
Organization: School of Computer Science, Carnegie Mellon


My friend Dan Masys writes:

> Welcome to the stark realities of twin engine operation.  There are a
> number of GA twins (most, actually) which have a (usually brief) flight
> mode where, upon losing an engine (which, if it cannot be feathered for one
> reason or another) all you can do is stall and crash.  This past weekend
> a neighbor down the street (a competent cardiologist and competent multi
> pilot) could not maintain control of his Piper Aerostar in an engine out
> situation and crashed at the Sussex Country airport in MD, killing himself
> his daughter and her husband.  I think the Aerostar may be something of
> a worst case, but the msg is that it happens, skill and experience
> notwithstanding.

Dan, I think your comments are misleading.

When you lose an engine on takeoff in a twin, you *always* have the option
to retard both throttles and land straight ahead, taking your lumps just
like a single-engine pilot would.  I don't believe any light or medium
piston twin becomes uncontrollable the instant an engine quits.  There is
no excuse for stalling a twin after an engine failure.

It is certainly true that a multi pilot can kill himself if he *insists* on
holding altitude no matter what.  If you can't get the prop to feather, or
the gear won't come up, or the flaps won't retract, or you're operating
above the airplane's single engine service ceiling, then you're not going to
be able to maintain altitude at blueline airspeed.  (Blueline, or Vyse, is
the single-engine best rate of climb speed.)  A competent multi pilot will
accept a gradual descent and look for a place to put the plane down safely.

But if a pilot who is not current on engine-out procedures panics, he may
believe that the airplane *has* to maintain altitude no matter what, and
thus keep hauling back on the stick until the airspeed bleeds off and the
plane stalls or directional control is lost.  It's an easy mistake to make.

At Piper school one of the instructors told a story about losing an engine
in a twin just after takeoff from Vero Beach.  He got the airplane cleaned
up but the climb rate was very slight.  He was still low to the ground, so
he told the tower he was just going to fly runway heading for *several miles*
until he was high enough to feel comfortable making a turn back toward the
airport.  And that's what he did.

There is no substitute for recurrent training in a twin.  Unfortunately, the
situation pilots most need to practice:  catastrophic engine failure just
after takeoff, is so dangerous that they can't really practice it.
Actually, some do practice it, but it's a very bad idea.  The next best
thing is to practice engine cuts at a safe altitude, including during
simulated takeoff (conducted at altitude), and engine-out instrument
approaches under the hood.

Twin engine emergency procedures *must* be practiced regularly.  No matter
how skillful a pilot appears to be with both engines running, when one quits
it's an entirely different story.

I just finished 1 of the 3 required hours of recurrent training for my Phase
V wings.  This was the instrument hour.  We did an ILS, NDB, and VOR
approach, including simulated engine falures outside the FAF for the ILS and
VOR approaches -- which were completed to touchdown.  We also did holding, a
procedure turn, and a go-around under the hood.  Slowly I could feel the
rust dissolve away.  I'm looking forward to the next 2 hours.  

-- Dave Touretzky,  CFI-AIM,  Seneca N8147E (``The Recurrent Beast'')

PS: for people wondering about the advantages of having a second engine,
remember that you spend very little time in takeoff configuration; most of
your time is spent in cruise.  An engine failure in cruise is no big deal to
a twin driver.  It's something to think about when you're flying over a
large body of water, or hazardous terrain, or in hard IMC at night.
Newsgroups: rec.aviation