A Double Immelmann
without rolls. Graphic
courtesy of NSRCA.
The 2015 Treasure Valley Pattern Contest included four Sportsman pilots.
401-6 Double Immelmann without Rolls (U)
From upright, pull a 1/2 inside loop to level inverted flight, hesitate, pull a 1/2 inside loop to exit upright at
the entry altitude. The horizontal legs should be equal to the diameter of the loops. The first 1/2 loop is
initiated at a distance of half the loop diameter past the centerline.
➢ Half loops not of constant and same radius.
➢ Half loops not completed exactly above or
below point of commencement of half loops.
➢ Changes in track during half loops or lines.
➢ Entry and exit not at same altitude.
1/2 loop 1/2 loop
Same as loop diameter.
After the outside wing comes over
the top, reduce throttle to idle. Many
airplanes require a small amount of
opposite aileron as the airplane pivots.
Whether pivoting in or out, points will
be deducted if the wings do not remain
perpendicular to the runway during the
As the nose drops to vertical, slowly
ease the rudder. Gradually match the
downline heading to the crab angle used
in the upline. During the downline is
another opportunity to make minor,
sneaky, adjustments. Note that as the
airspeed increases, the crab angle lessens.
Pull the airplane level with the same
radius used when pulling vertical. Bring
the throttle to its cruise setting, rolling
the wings into the wind to level them.
As discussed in the last column, the
pull offers an opportunity to skid the
airplane in or out of the box, using the
rudder to control the skid and ailerons to
keep the wings level.
Breathe: Take a deep breath as the
airplane flies straight and level toward
the center of the box.
Double Immelmann: Here’s a funny
story. A few years ago we held a club
Pattern contest. All seven contestants
flew the Sportsman sequence. I’ll
never forget hearing a caller call
“Double Immelmann” and the pilot
responding, “What the heck is a Double
Immelmann?” as he flew through the
box and out the other end.
One of the most misunderstood
sportsman maneuvers is the Double
Immelmann, a square box with half
loops on the ends.
The easiest way to time a Double
Immelmann is by counting. As the
pole, count one
perform a nice
round half loop
to inverted. Make
the diameter of the half loop twice the
distance the airplane travels during the
one Mississippi count.
When inverted, count one Mississippi,
two Mississippi, and perform another
wind-corrected half loop to upright,
straight, and level. Easy, right?
Remember, when the airplane is
crabbing into the wind, use the same
roll-into-the-wind technique used in the
stall turn, maintaining level wings and a
parallel flight path.
Many people have trouble with the
top inverted segment. I know I do. Trying
to remember down is up, wings are
level, and counting is a huge workload—
104 Model Aviation SEPTEMBER2015 www.ModelAviation.com