HELICOPTER Flashcards
Because of lift differential due to differing rotational relative wind values along the blade, the blade should be designed with a TWIST to alleviate internal blade stress and distribute the lifting force more evenly along the blade.
BLADE TWIST
Because of lift differential due to differing rotational relative wind values along the blade, the blade should be designed with a
TWIST to alleviate internal blade stress and distribute the lifting force more evenly along the blade.
provides higher pitch angles at the root where velocity is low and lower pitch angles nearer the tip where velocity is higher.
BLADE TWIST
This increases the induced air velocity and blade loading near the inboard section of the blade.
BLADE TWIST
Blade twist sections
SECTION NEAR ROOT
SECTION IN CENTER
SECTION NEAR TIP
TRUE/FALSE
“More nose-down” tilt to blade section closer to tip
TRUE
TRUE/FALSE
“Less nose-down” tilt to blade section closer to tip
FALSE
TRUE/FALSE
“More nose-down” tilt to blade section further to tip
FALSE
on the mast, the attaching point for the root of the blade, and the axis about which the blades rotate.
HUB
the farthest outboard section of the rotor blade
TIP
the inner end of the blade and is the point that attaches to the hub
ROOT
the change in blade incidence from the root to the outer blade
TWIST
Helicopters are used for many different reasons and they may be the most ______vehicle in the world
versatile
A helicopter can do it all: 1._____,2._____3.______4._____________
From leg-like skids to electric tail rotors, it will be interesting to see how much further the helicopter develops.
- hover
- land on uneven ground
- travel vertically
- horizontally and every other direction in between
two main types of engine
reciprocating engine, turbine engine
use one or more pistons to convert pressure into a rotating motion creating power
reciprocating engine
use a process of pressurized air mixed with fuel to create high-velocity gas to turn the turbine wheels
turbine engine
It has a better power-to-weight ratio.
turbine engine
the fastest known speed of a helicopter is ___ knots
225 knots
Comes in different forms but skids and wheels are the most common.
landing gear
Most common landing gear
skids and wheels
Fairly common landing gears
bear paws, floats, and pontoons
are attached to the skids and used for helicopters landing off airport on uneven, unstable and soft terrain helping with overall stability
bear paws
In what year did DARPA introduced a robotic landing gear that could fold like legs, making landing or uneven terrain much easier
2015
DARPA
Defence Advanced Research Projects Agency
The longest helicopter flight without landing was _____ miles
2,213 miles
Found at the tail end of a helicopter and its primary function is to counteract the torque effect by the main rotor.
tail rotor
If it weren’t there, the helicopter would spin in the opposite direction of the main rotor.
tail rotor
It can have 8-13 blades but are significantly quiter than traditional tail rotors
Fenestron
Have been explored as an option to replace the traditional tail rotors, which would be better for the environment,
Electrical tail rotors
ETR
electrical tail rotor
The most important part of the helicopter. It lets the pilot control which way they turn, change altitude and move laterally. The pilot manipulates these with controls in the cockpit that are linked to the swash plate assembly.
main rotor
Rotor blades were made out of _______ and _____ until the 1960s
laminated wood and fabric
He holds the patent for the rotor mast from 1965
Trench Charles Henry
The central control unit determines all activity of the helicopter. The pilot sits in the cockpit with a co-pilot; helicopters not requiring 2 pilots can have another person in the front seat.
cockpit
Four main controls a helicopter pilot must use in flight:
cyclic, collective, anti-torque pedals, and throttle
In the ____ cockpit was used as a ______term before being used as an aviation one
1700s, sailing
The first reference to an aircraft as having a cockpit was during ______, referring to the small enclosure
World War II
PARTS OF A HELICOPTER
Cockpit
Main rotor
Tail roto
Landing gear
Engine
a rotor-controlled aircraft with a complex anatomy.
helicopter
Although it is smaller than an airplane, the fast spinning rotors makes it much more difficult to control.
helicopter
