T-34C OUT-OF-CONTROL FLIGHT
The spiral is characterized by a nose-low attitude, high roll rates, and rapidly increasing airspeed.
A spiral may easily be confused with a spin if the pilot relies solely on the interpretation of
outside references and fails to accomplish a proper analysis of the cockpit flight instruments.
Should the pilot misinterpret a spiral as a spin, it is highly unlikely that anti-spin inputs will
affect a successful recovery.
If performed to the left, the cockpit indications will initially look like those of a Steady-State
Erect Spin, with AOA pegged, airspeed moving into the 80 - 100 knot range, and turn needle
fully deflected left. However, the aircraft is not stalled. This becomes apparent if the spiral is
performed to the right, which makes the AOA hover near 20 units. Even when performed to the
left, the airspeed will soon accelerate through the 80 - 100 knot range and positively indicate the
aircraft is not in a spin. Airspeed will continue to accelerate with a rapid rate of rotation until the
only method of recovery is effected, NATOPS OCF Recovery Procedures. Once the controls
have been neutralized and the absence of spiral indications is confirmed, the pilot must recover
from a nose-low, unusual attitude. Having the power reduced to idle will help slow the rate of
airspeed increase. Excessive airspeed creates a strong tendency for the nose to pitch upward.
This tendency is exaggerated when the aircraft is trimmed for a slower airspeed (i.e., 150 KIAS).
It is critical to emphasize, the pilot must stop the roll and level the wings prior to allowing the
nose to pitch upward. This will prevent a rolling pullout, which imposes additional stress on the
airframe. Failure to prevent a rolling pullout could result in structural failure of the aircraft due
to asymmetrical "G" loading. Prior to attempting a pullout, ensure the wings are level by
referencing the horizon and do not exceed 24 units AOA or 4.5 "G's" (altitude permitting).
The key to a safe recovery from an inadvertent spiral lies in the expeditious recognition of the
aircraft's actual flight condition. The pilot must be able to accomplish a proper analysis of the
cockpit flight instruments and not rely solely on outside references.
208. T-34C ERECT SPIN CHARACTERISTICS
If pro-spin controls are maintained through the PSG phase, a spin will develop. Spin is
characterized by stable pitch attitudes, AOA, vertical velocity, airspeed, and yaw rates. Cockpit
indications of an erect spin are: Airspeed - stabilized between 80 - 100 KIAS, AOA - 30 units,
turn needle - fully deflected in direction of spin. Other characteristics include approximately 45°
nose down attitude, a spin rate of 110 - 170 degrees per second, and a 9000 - 12,000 fpm rate of
descent. The Incipient Spin will precede the fully developed spin, with some oscillations in all
Positive recovery controls should be utilized for fully developed spins. If the controls are simply
released, aerodynamic loads will hold the elevator full aft for several turns; the ailerons and
rudder may "float" to near neutral. To neutralize the elevator, a moderate but definite forward
force (approximately 40 lbs. for the T-34C) will be required to overcome the aerodynamic load.
Positive control neutralization may occasionally result in a recovery, but in most cases, the
recovery is slow and may not occur. With anti-spin controls maintained, recovery will occur in
1 - 2 1/2 turns.
UNUSUAL ATTITUDES AND OUT-OF-CONTROL FLIGHT 2-9