Federal Aviation Administration, DOT

Pt. 60, App. D

kpayne on VMOFRWIN702 with $$_JOB

the helicopter data. The procedure for evaluating the response is illustrated in Figure 1
of this attachment.
(c) Critically Damped and Overdamped Response. Due to the nature of critically
damped responses (no overshoots), the time
to reach 90 percent of the steady state (neutral point) value must be the same as the
helicopter within Section10 percent. The simulator
response must be critically damped also.
Figure 2 of this attachment illustrates the
procedure.
(d) Special considerations. Control systems
that exhibit characteristics other than classical overdamped or underdamped responses
should meet specified tolerances. In addition, special consideration should be given to
ensure that significant trends are maintained.
(2) Tolerances.

(a) The following summarizes the tolerances,  - T -  for underdamped systems, and
 - n -  is the sequential period of a full cycle of
oscillation. See Figure D2A of this attachment for an illustration of the referenced
measurements.
T(P0) Section10% of P0
T(P1) Section20% of P1
T(P2) Section30% of P2
T(Pn) Section10(n + 1)% of Pn
T(An) Section10% of A1
T(Ad) Section5% of Ad = residual band
Significant overshoots First overshoot and
Section1 subsequent overshoots
(b) The following tolerance applies to critically damped and overdamped systems only.
See Figure D2B for an illustration of the reference measurements:
T(P0) Section10% of P0

457

VerDate Sep<11>2014

16:30 Jun 25, 2019

Jkt 247047

PO 00000

Frm 00467

Fmt 8010

Sfmt 8002

Q:\14\14V2.TXT

PC31