Meatball Multi-Engine Takeoff
Anyone who flies multi-engine airplanes is going to be nauseatingly familiar with the emergency scenario of an engine failure. This article concerns itself solely with piston multi-engine aircraft, which have hardly any excess thrust available with only one engine operating. Turbine aircraft have awesome thrust and turbo-props often have auto-feather.
When an engine failure in a piston twin occurs in cruise or descent, you have lots of time to deal with it, because you have lots of energy in the form of airspeed and altitude.
However, when an engine fails shortly after takeoff, you’re in a world of hurt because you have very little airspeed and very little altitude. This means you have very little time to do the right thing to avoid dying.
In Canada, we are supposed to teach multi-engine flying according to TP11575E, the Instructor Guide for the Multi-Engine Rating. Here’s what it says to do if you have an engine failure after takeoff:
CONTROL
yaw, roll, airspeed
POWER
mixtures rich, propellers FULL
increase, throttles FULL power
DRAG
check landing gear up, flaps
up
IDENTIFY
failed engine
VERIFY
failed engine by reducing
throttle of suspected failed engine
FEATHER
the propeller on the failed
engine
SECURE
complete checklist when time and
altitude permit
LAND
if an airport is not suitable,
then proceed to the nearest suitable airport
If you actually tried to do this at low altitude in a piston
twin after an engine failure after takeoff, you would surely die. In cruise or descent, there is time for this,
but not immediately after takeoff.
My reluctance to embrace death in a piston twin lead to the
development of the Meatball Multi-Engine Takeoff for Piston Twins. It’s not something to be proud of, and I don’t
recommend you do it, but I thought you might find it interesting as to how I
stay alive during a takeoff in a piston twin:
Fuel Tanks – selection/quantity
Fuel Boost Pumps – as required
Props – full forward
Mixtures – full rich
Engine Quadrant Friction
Lock – secure
Flaps – up
Throttles up with brakes
on - over clean pavement, 20-25 in MP
Release brakes,
throttles full forward
Rotate, climb at Vyse
(blue line on ASI)
Once you have a positive rate of climb, move your right hand
from the throttles to the gear selector and select gear up. Now move your right hand to the prop
controls. The friction lock should hold
the throttles full forward – you set it before takeoff, remember?
Now let’s look at various engine failure scenarios.
If an engine fails at very low altitude, before you move your
right hand from the throttles to the gear selector, push the nose down to
maintain airspeed, and simply pull both throttles back and land on the
remaining runway. If you have lots of
runway left, you should be able to land with no damage to the airframe. The gear is still down, remember? If you took off from a short runway your
landing might not be pretty, but you and your passengers will do better than if
you had elected to continue the takeoff.
In the above scenario I have deliberately decided against going
aviating in a piston twin with only one engine, with the gear down and one
engine windmilling and producing drag.
You aren’t going to be able to maintain a positive rate of climb with
all that drag, and you don’t have time to get rid of all that drag, so it’s
best to land sooner, under control. It’s
always best to land under control.
Let’s look at another engine failure scenario, occurring a bit
later. You’ve selected gear up, and
moved your right hand immediately to the prop controls – NOT the
throttles. The reason for this is that
if you have an engine failure under 500 AGL, there is no time to fart
about. You need to reduce drag
immediately and configure the aircraft perfectly if you are to maintain even
100 fpm of climb, which is pretty pitiful.
So, an engine failure below 500 AGL occurs shortly after you
have selected gear up and then moved your right hand to the prop controls. If the aircraft yaws right, immediately pull
the right prop lever all the way back.
If the aircraft yaws left, immediately pull the left prop lever all the
way back. This will configure the
aircraft for minimum drag – engine-out prop feathered, gear up, flaps up.
99.999% of the time, the above is the best choice. However, there is a rare possibility of a
prop governor failure resulting in an overspeed. The meatball procedure above will result in
you feathering the good engine, which is horrible. But with a real engine failure, in addition
to the THRUM THRUM of the props out of sync, you will get an airspeed loss
which results in a feeling of deceleration as you move forward when the engine
fails. You don’t get that with an
overspeed.
One thing I cannot emphasize enough after an engine failure:
LOWER THE NOSE
This is something which is often skipped during an engine
failure during a climb, with hideous results as the airspeed decreases from
blue line (Vyse) to red line (Vmc). If you
maintain the same deck angle as you had with two engines turning, the airspeed
WILL decrease below red line and you will roll inverted as your rudder loses
effectiveness and you yaw uncontrollably into the dead engine, killing yourself
and your passengers.
You must LOWER THE NOSE to maintain blue line airspeed, which is
essential. When one engine fails, you
have very little excess thrust available and simply cannot continue to climb
with the pitch angle you had with two engines.
To actually achieve a whopping 100 (no typo) fpm climb rate on the
VSI, remember to bank into the good engine ever so slightly – less than 5
degrees. 2 or 3 degrees is better, and
have the ball half out of the cage to avoid a drag-producing sideslip. The technical reasoning behind this is worthy
of an article its own – see my AvWeb Multi-Engine Aircraft article from all
those years ago, for more information about this.
At this point, you’ve done your best to configure the aircraft
for minimum drag and maximum performance.
Circle around and land immediately on the first available suitable
(wind, length) runway. You probably don’t
want to know which direction I’m going to turn.
Enough blatant heresy for one article.
Transport hates me enough already.
Again, I can’t recommend this procedure for anyone else. DON’T DO IT.
It’s contrary to TP 11757E and thus must be wrong. However, it’s what I have done for decades,
and will continue to do, because I really don’t want to die any time soon.
--
acboyd@gmail.com Nov 2011