ХАРАКТЕРИСТИКИ НА УПРАВЛЯЕМОСТ ПРИ ДВИЖЕНИЕ ПО ЗЕМЯ И ПО ВОДА

The rotorcraft must be designed to withstand

the loads that would occur when the rotorcraft is

taxied over the roughest ground that may

reasonably be expected in normal operation.

If certification for water operation is requested,

no spray characteristics during taxying, take-off,

or landing may obscure the vision of the pilot or

damage the rotors, propellers, or other parts of the

rotorcraft.

The rotorcraft may have no dangerous tendency

to oscillate on the ground with the rotor turning.

Изисква се ророркрафтът да няма опасната тенденция да трепти на земята при въртящ се винт.

Each part of the rotorcraft must be free from

excessive vibration under each appropriate speed

and power condition.

(a) Strength requirements are specified in

terms of limit loads (the maximum loads to be

expected in service) and ultimate loads (limit

loads multiplied by prescribed factors of safety).

Unless otherwise provided, prescribed loads are

limit loads.

(b) Unless otherwise provided, the specified

air, ground, and water loads must be placed in

equilibrium with inertia forces, considering each

item of mass in the rotorcraft. These loads must

be distributed to closely approximate or

conservatively represent actual conditions.

(c) If deflections under load would

significantly change the distribution of external or

internal loads, this redistribution must be taken

into account.

.

(а) Якостните изисквания са дефинирани чрез експлоатационни натоварвания (мак­сималните натоварвания, които могат да се очакват в експлоатация) и разрушаващи натоварвания (експлоатационни натоварвания, умножени с предписан коефициент на сигурност). Предписваните натоварвания са гранични, освен ако не е указано друго.

(b) Въздушните, наземните и водните натоварвания трябва да бъдат поставени в равновесие с инерционните сили, отчитайки масата на всеки елемент във ророркрафта, освен ако не е упоменато друго. Тези натоварвания трябва да бъдан разпределени, за да апроксимират приблизително или да представят точно действителните условия.

(с) Ако деформациите при натоварване биха променили значително разпределението на външните или вътрешните натоварвания, това преразпределение трябва да се отчете.

Unless otherwise provided, a factor of safety of

1.5 must be used. This factor applies to external

and inertia loads unless its application to the

resulting internal stresses is more conservative.

(a) The structure must be able to support

limit loads without detrimental or permanent

deformation. At any load up to limit loads, the

deformation may not interfere with safe operation.

(b) The structure must be able to support

ultimate loads without failure. This must be

shown by –

(1) Applying ultimate loads to the

structure in a static test for at least 3 seconds;

or

(2) Dynamic tests simulating actual

(a) Compliance with the strength and

deformation requirements of this Subpart must be

shown for each critical loading condition

accounting for the environment to which the

structure will be exposed in operation. Structural

analysis (static or fatigue) may be used only if the

structure conforms to those structures for which

experience has shown this method to be reliable.

In other cases, substantiating load tests must be

made.

(b) Proof of compliance with the strength

(1) Dynamic and endurance tests of

rotors, rotor drives, and rotor controls;

(2) Limit load tests of the control

system, including control surfaces;

(3) Operation tests of the control

system;

(4) Flight stress measurement tests;

(6) Any additional tests required for

new or unusual design features.

The following values and limitations must be

established to show compliance with the structural

requirements of this Subpart:

(a) The design maximum weight.

(b) The main rotor rpm ranges power on and

power off.

(c) The maximum forward speeds for each

main rotor rpm within the ranges determined in

sub-paragraph (b) of this paragraph.

(d) The maximum rearward and sideward

flight speeds.

(e) The centre of gravity limits

corresponding to the limitations determined

paragraph.

(f) The rotational speed ratios between each

powerplant and each connected rotating

component.

(g) The positive and negative limit

manoeuvring load factors.

Следните стойности и ограничения трябва да се установят за доказване на съответствие със конструктивните изисквания на настоящия подраздел:

(а) Максималното проектно тегло;

(b) Диапазоните на оборотите в минута на носещия винт с обран и необран режим на мощност;

(с) Максималните постъпателни скорости за всички обороти в минута на носещия винт в рамките на диапазоните, определени по смисъла на подпараграф (b) на настоящия параграф;

(d) Максималните скорости на полета назад и настрани.

(е) Ограниченията на центъра на тежестта , съответстващи на ограниченията, определени в подпараграфи (b), (с) и (d) на настоящия параграф.

(f) Коефициентите на ротационната скорост между всяка силова установка и всеки свързан въртящ се компонент.

(g) Положителната и отрицателната граница на коефициентите на натоварване при маневриране.

(a) The flight load factor must be assumed to

act normal to the longitudinal axis of the

rotorcraft, and to be equal in magnitude and

opposite in direction to the rotorcraft inertia load

factor at the centre of gravity.

(b) Compliance with the flight load

requirements of this Subpart must be shown –

(1) At each weight from the design

minimum weight to the design maximum

weight; and

(2) With any practical distribution of

disposable load within the operating limitations

in the Rotorcraft Flight Manual.