flight instruments uni

8/7/2019 flight instruments uni

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Flight Instruments


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AVIATOR


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What is an Aviator


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History

These early planes had noinstruments, radios, or othernavigational aids. Pilots flew bydead reckoning or "by the seat oftheir pants." Forced landingsoccurred frequently because ofbad weather, but fatalities in those

early months were rare, largelybecause of the small size,maneuverability, and slow landingspeed of the planes.


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Cockpit

cockpit or flight deck is the area,usually near the front of an aircraft,from which a pilot controls theaircraft. Most modern cockpits areenclosed, except on some smallaircraft, and cockpits on largeairliners are also physically

separated from the cabin. From thecockpit an aircraft is controlled onthe ground and in the air.
http://en.wikipedia.org/wiki/Aircrafthttp://en.wikipedia.org/wiki/Airlinerhttp://en.wikipedia.org/wiki/Airlinerhttp://en.wikipedia.org/wiki/Aircraft


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Cockpit as a term for the pilot'scompartment in an aircraft first appearedin 1914. From about 1935 cockpit also

came to be used informally to refer to thedriver's seat of a car, especially a highperformance one, and this is officialterminology in Formula One. The term ismost likely related to the sailing term for

the coxswain's station in a Royal Navyship, and later the location of the ship'srudder controls.


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Cockpit


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1936 de Hollander HornetMoth cockpit


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The cockpit of an aircraft contains flightinstruments on an instrument panel, and thecontrols which enable the pilot to fly the aircraft.In most airliners, a door separates the cockpit

from the passenger compartment. After theSeptember 11, 2001 terrorist attacks, all majorairlines fortified the cockpit against access byhijackers.

On an airliner, the cockpit is usually referred to asthe flight deck. This term derives from its use bythe RAF for the separate, upper platform wherethe pilot and co-pilot sat in large flying boats


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Ergonomics

The first airplane with an enclosed cabin appeared in 1913on Igor Sikorsky's airplane The Grand. However, during the 1920s there were many passenger

aircraft in which the crew were open to the air while thepassengers sat in a cabin.

Military biplanes and the first single-engined fighters and

attack aircraft also had open cockpits into the Second WorldWar. Early airplanes with closed cockpits were the 1924 Fokker

tri-motor, the 1926 Ford Tri-Motor, the 1927 Lockheed Vega,the Spirit of St. Louis, the 1931 Taylor Cub, German Junkersused as military transports, and the passenger aircraft

manufactured by the Douglas and Boeing companies duringthe mid-1930s. Open-cockpit airplanes were almost extinct by the mid-

1950s, with the exception of training planes and crop-dusters.


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Basic Six

The layout of the cockpit, especially inthe military fast jet, has undergonestandardization, both within and between

aircraft different manufacturers and evendifferent nations.

One of the most important developmentswas the Basic Six pattern, later the

Basic T, developed from 1937 onwardsby the Royal Air Force, designed tooptimize pilot instrument scanning


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Six basic instruments in a light twin-engine airplane arranged ina "basic-T". From top left: airspeed indicator, attitude indicator,altimeter, turn coordinator, heading indicator, and vertical speed

indicator


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Basic Six in Commercial

This panel arrangement was incorporated intoevery RAF aircraft, from the light Tiger Moth, tothe heavy Avro Lancaster, and minimized thetype-conversion difficulties associated with Blind

Flying, since a pilot trained on one aircraft couldquickly become accustomed to any other if theinstruments were identical.

This Basic Six set was also adopted bycommercial aviation. After the Second World Warthe arrangement was changed to: (top row)airspeed, artificial horizon, altimeter, (bottom row)radio compass, direction indicator, vertical speed.


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Ergonomics and human factors concernsare important in the design of moderncockpits.

The layout and function of cockpitdisplays controls are designed toincrease pilot situation awarenesswithout causing information overload.

In the past, many cockpits, especially infighter aircraft, limited the size of thepilots that could fit into them. Now,cockpits are being designed to

accommodate all sizes.


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In the design of the cockpit in a military fast jet, the traditionalknobs and dials associated with the cockpit are mainly absent.

Instrument panels are now almost wholly replaced by electronicdisplays which are themselves often re-configurable to save

space. While some hard-wired dedicated switches must still beused for reasons of integrity and safety, many traditionalcontrols are replaced by multi-function re-configurable controlsor so-called soft keys. Controls are incorporated onto the stickand throttle to enable the pilot to maintain a head-up and eyes-

out position the so-called Hands On Throttle And Stick orHOTAS concept,. These controls may be then further augmented by new control

media such as head pointing with a Helmet Mounted SightingSystem or Direct Voice Input (DVI).

New advances in auditory displays even allow for Direct VoiceOutput of aircraft status information and for the spatiallocalisation of warning sounds for improved monitoring ofaircraft systems. A central concept in the design of the cockpitis the Design Eye Position or "DEP".


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Helmet Mounted Sights


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Direct Voice Input Direct Voice Input (DVI) (also sometimes calledVoice Input Control (VIC)) is a style of Human-

Machine Interaction "HMI" in which the user makesvoice commands to issue instructions to the machine.

It has found some usage in the design of the cockpit ofseveral modern military aircraft, particularly the Eurofighter, the F-35 Lightning II, the Rafale and the JAS39 Gripen, having been trialled on earlier fast jets suchas the Harrier AV-8B and F-16 VISTA.

A study has also been undertaken by the RoyalNetherlands Air Force using voice control in a F-16simulator.

DVI systems may be "user-dependent" or "user-independent". User-dependent systems require apersonal voice template to be created by the pilotwhich must then be loaded onto the aircraft beforeflight. User-independent systems do not require anypersonal voice template and will work with the voice ofany user.


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The layout of control panels in modern airlinershas become largely unified across the industry.

The majority of the systems-related controls(such as electrical, fuel, hydraulics and

pressurization) for example, are usually locatedin the ceiling on an overhead panel.

Radios are generally placed on a panel betweenthe pilot's seats known as the pedestal.Automatic flight controls such as the autopilot are

usually placed just below the windscreen andabove the main instrument panel on theglareshield.


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Back-up instruments

In a less prominent part of thecockpit, in case of failure of the

other instruments, there will be aset of back-up instruments,showing basic flight informationsuch as Speed, Altitude, Heading,

and aircraft attitude.


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Aerospace industrytechnologies

In the U.S. the Federal AviationAdministration (FAA) and the NationalAeronautics and Space Administration

(NASA) have researched the ergonomicaspects of cockpit design and haveconducted investigations of airlineindustry accidents. Cockpit designdisciplines include Cognitive Science

(internal mental processes),Neuroscience, Human ComputerInteraction, Human Factors Engineering,Anthropometry (study of human body)and Ergonomics.


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Aircraft designs have adopted the fullydigital glass cockpit. In such designs,instruments and gauges, includingnavigational map displays, use a userinterface markup language.

This standard defines the interface betweenan independent cockpit display system,

generally produced by a singlemanufacturer, and the avionics equipmentand user applications which it if required tosupport, by means of displays and controls,often made by different manufacturers.

The separation between the overall displaysystem, and the applications driving it,allows for considerable specialization andindependence.


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Flight Instruments at a Glance

artificial horizon to show the pilot


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artificial horizon to show the pilotthe airplanes position in relation

to the ground.

Here, the airplane is banking leftwith its nose on the horizon where brown ground meets

blue sky.

BASIC INSTRUMENTS

The airspeed indicator shows


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The airspeed indicator showsspeed through the air--- not overthe ground.

The pitot tube on thewing catches on-rushing air. This ram

air is compared to

static air to

determine air speed.

The static portmeasures static or

still air air that isnot affected by theairplanes speed

through the air

BASIC INSTRUMENTS

pressure outside the airplane and


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pressure outside the airplane andcompares it to air pressure at sea

level to determine altitude.

Like the hands of a clock, the longhand shows smaller increments(100s of feet) while the shorter hand

shows larger increments (1,000s offeet).

This altimeter is reading 1720 feet.

BASIC INSTRUMENTS

the wings are level or banked


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the wings are level or banked.The position of the ball indicates

if the airplane is turning properly.

The ball is centered whenthe turn is balanced by rudder

Turn Coordinator

BASIC INSTRUMENTS


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Gimbal


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The heading indicator displays


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The heading indicator displaysthe direction of flight.

BASIC INSTRUMENTS

This airplane is heading southat 175 degrees.

The vertical speed indicator uses


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The vertical speed indicator useschanges in air pressureto indicate rate of climb or

descent.

Airplane is descending at 190feet per minute

BASIC INSTRUMENTS

o s use ra os o


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o s use ra os ocommunicate with airtraffic control and otherpilots. Other radios alsoare used to navigateusing ground stationsor satellites.

COMMUNICATION


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Pilots increasingly use GPS


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Pilots increasingly use GPSsatellite navigation to display

position and ground speed, locatenearby airports, and plot course,distance and time to any

destination

Top: GPS can be small,

handheld and portable.

Bottom: Flat-panel GPS moving maps and

flight displays are just the ones in airlinersand some cars.

There are plenty of


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There are plenty ofthings to learnINSIDE THE COCKPITOF AN AIRPLANE


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Instrumentation

Pitot-static system

Altimiter

Vertical Speed Indicator

Airspeed Indicator Gyroscopic Instruments

Turn coordinator

Artificial horizon

Heading indicator

Magnetic Compass

OAT Gauge


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Other instruments that might beconnected are air data computers, flightdata recorders, altitude encoders, cabin

pressurization controllers, and variousairspeed switches.

Errors in pitot-static system readings canbe extremely dangerous as theinformation obtained from the pitot static

system, such as altitude, is often criticalto a successful flight.

Several commercial airline disastershave been traced to a failure of the pitot-static system.

A Typical Electrically Heated Pitot-Static Head


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A Typical Electrically Heated Pitot-Static Head


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A Typical Pitot-Static System


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A Typical Pitot-Static System.


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Examples of pitot tube, statictube, and pitot-static tube.


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The pitot-static system of instrumentsuses the principle of air pressuregradient.

It works by measuring pressures orpressure differences and using thesevalues to assess the speed and altitude.

These pressures can be measured eitherfrom the static port (static pressure) orthe pitot tube (pitot pressure).

The static pressure is used in allmeasurements, while the pitot pressureis only used to determine airspeed.

Pit t


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Pitot pressure The pitot pressure is obtained from the pitot

tube. The pitot pressure is a measure of ram airpressure (the air pressure created by vehiclemotion or the air ramming into the tube), which,under ideal conditions, is equal to stagnationpressure, also called total pressure.

The pitot tube is most often located on the wing

or front section of an aircraft, facing forward,where its opening is exposed to the relativewind.

By situating the pitot tube in such a location, theram air pressure is more accurately measured

since it will be less distorted by the aircraft'sstructure. When airspeed increases, the ram air pressure

is increased, which can be translated by theairspeed indicator.

Static pressure


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Static pressure The static pressure is obtained through a static port. The

static port is most often a flush-mounted hole on the fuselageof an aircraft, and is located where it can access the air flow

in a relatively undisturbed area. Some aircraft may have asingle static port, while others may have more than one.

In situations where an aircraft has more than one static port,there is usually one located on each side of the fuselage.With this positioning, an average pressure can be taken,

which allows for more accurate readings in specific flightsituations.

An alternative static port may be located inside the cabin ofthe aircraft as a backup for when the external static port(s)are blocked. A pitot-static tube effectively integrates the staticports into the pitot probe. It incorporates a second coaxial

tube (or tubes) with pressure sampling holes on the sides ofthe probe, outside the direct airflow, to measure the staticpressure.


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Multiple pressure

Some pitot-static systems incorporatesingle probes that contain multiplepressure-transmitting ports that allow for

the sensing of air pressure, angle ofattack, and angle of sideslip data.Depending on the design, such air dataprobes may be referred to as 5-hole or 7-

hole air data probes. Differentialpressure sensing techniques can beused to produce angle of attack andangle of sideslip indications.


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Gyroscopic Principles

Rigidity in spaceAxis of rotation points in a

constant directionregardless of the position

of its base.

PrecessionTilting or turning of a gyro in

response to a deflectiveforce.


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Internal mechanism of anairspeed indicator
http://en.wikipedia.org/wiki/File:Airspeed_Mech.SVG


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The pitot-static system obtains pressures forinterpretation by the pitot-static instruments. Whilethe explanations below explain traditional,mechanical instruments, many modern aircraft use

an air data computer (ADC) to calculate airspeed,rate of climb, altitude and Mach number.

In some aircraft, two ADCs receive total and staticpressure from independent pitot tubes and staticports, and the aircraft's flight data computer

compares the information from both computersand checks one against the other. There are also "standby instruments", which are

back-up pneumatic instruments employed in thecase of problems with the primary instruments.


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The airspeed indicatoror airspeed gauge is aninstrument used in anaircraft to display thecraft's airspeed, typicallyin knots, to the pilot.
http://en.wikipedia.org/wiki/File:True_airspeed_indicator.svg


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Use of ASI

The airspeed indicator is used by the pilot duringall phases of flight, from take-off, climb, cruise,descent and landing in order to maintainairspeeds specific to the aircraft type and

operating conditions as specified in the OperatingManual.

During instrument flight, the airspeed indicator isused in addition to the Artificial horizon as aninstrument of reference for pitch control duringclimbs, descents and turns.

The airspeed indicator is also used in deadreckoning, where time, speed, and bearing areused for navigation in the absence of aids suchas NDBs, VORs or GPS.


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The difference between the pitot pressure andthe static pressure is called "impact pressure".The greater the impact pressure, the higher theairspeed reported. A traditional mechanicalairspeed indicator contains a pressure diaphragm

that is connected to the pitot tube. The casearound the diaphragm is airtight and is vented tothe static port. The higher the speed, the higherthe ram pressure, the more pressure exerted onthe diaphragm, and the larger the needlemovement through the mechanical linkage. tight

and is vented to the static port. The higher thespeed, the higher the ram pressure, the morepressure exerted on the diaphragm, and thelarger the needle movement through themechanical linkage.


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On light aircraft

Airspeed indicator markings use a set ofstandardized colored bands and lines onthe face of the instrument. The whiterange is the normal range of operating

speeds for the aircraft with the flapsextended as for landing or takeoff. Thegreen range is the normal range ofoperating speeds for the aircraft withoutflaps extended. The yellow range is the

range in which the aircraft may beoperated in smooth air, and then onlywith caution to avoid abrupt controlmovement.
http://en.wikipedia.org/wiki/Flap_(aircraft)http://en.wikipedia.org/wiki/Flap_(aircraft)


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Airspeeds color coded

VSO stall speed / minimumsteady flight in landingconfiguration (lower limit of whitearc)

VFE max. flap-extended speed

(upper limit of white arc)

VS1 stall speed in specifiedconfiguration (lower limit ofgreen arc)

VNO max. structural cruisingspeed (top of green arc, bottom

of yellow arc) VNE never exceed speed

(upper limit of yellow arc, markedin red)

A redline mark indicates VNE or velocity (never


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A redline mark indicates VNE, or velocity (neverexceed). This is the maximum demonstrated safeairspeed that the aircraft must not exceed under anycircumstances. The red line is preceded by a yellowband which is the caution area, which runs from VNO(maximum structural cruise speed) to VNE. A greenband runs from VS1 to VNO. VS1 is the stall speedwith flaps and landing gear retracted. A white bandruns from VSO to VFE. VSO is the stall speed withflaps extended, and VFE is the highest speed at whichflaps can be extended. Airspeed indicators in multi-

engine aircraft show a short radial red line near to thebottom of green arc for Vmc, the minimum indicatedairspeed at which the aircraft can be controlled with thecritical engine inoperative and a blue line for VYSE, thespeed for best rate of climb with the critical engineinoperative.


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Airspeeds, others

VLE max. landing gear-extended speed.

VA design maneuvering speed (flown inrough air or turbulence to prevent

overstressing airframe) VY Best rate-of-climb airspeed (creates

most altitude in a given period of time)

VX Best angle-of-climb speed (airspeedresulting in most altitude in a givendistance.)


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100 Knots =115 MPH

100 MPH = 87 knots


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V stands for Velocity VNE = Never Exceed Speed = Red Line

VA = Maneuvering speed


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VA = Maneuvering speedNot depicted on airspeed

indicator maneuvering speed, the speed at which

full and abrupt control movement can beapplied without the possibility of causingstructural damage, and, separately, the

maximum speed at which the aircraftcan be flown in turbulent conditions.

White Arc is Flap


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White Arc is FlapOperating Speed

Bottom of White Arc is VS0Stall speed with flapsfully extended

Top of the white arc isVfeMax flap extension speed


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Green arc is the normaloperating range

Bottom of Green band represents

Vs: The Stall speed with the flaps retracted

Top of the Green Band is VnoVno is maximum structural cruising speed

Yellow arc


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Yellow arcThe yellow range is the range in which the aircraft may be

operated in smooth air, and then only with caution to avoid

abrupt control movement.

Yellow arc = Vnothrough Vne


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V M l i d i


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Vy Most altitude inshortest amount of time

Cessna 172 Vy =74Kts

Best L/D


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Best L/D

Represents best GlideSpeedUsed for best gliding

speed if you have an engine failure

Best L/D in a Cessna 172 at grossweight is 68 Kts


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TAS True airspeedSpeed of wing through air mass

Ground speed


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Ground speedSpeed of aircraft relative to theground

TAS= 110Kts 15 Kt


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TAS= 110Kts -15 KtheadwindWhat is your groundspeed ?


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Airspeed gets input from


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Airspeed gets input fromPitot tube and static air

source


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Vso ?


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Vs ?


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Va ?


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Vno ?


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Vs ?


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Vfe ?


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Vne ?

T l b t l h ld fl


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To clear an obstacle you should flyat?VY

VX

Best L/D

VA


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To obtain maximum glide speed after

an engine failure you should fly at?VY

VX

Best L/D

VA


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In moderate turbulence you shouldfly at?VY

VXBest L/D

VA


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To climb to 5000 feet in the leastamount of time you should fly at?VY

VX

Best L/DVA


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Airspeed indicator


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speed d catomarkings for a light

multiengine airplane.
http://en.wikipedia.org/wiki/File:FAA-8083-3A_Fig_12-1.PNG


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Modern aircraft employing glass cockpitinstrument systems employ two airspeedindicators: an electronic indicator on theprimary flight data panel and a traditional

mechanical instrument for use if theelectronic panels fail. The airspeed istypically presented in the form of a "tapestrip" that moves up and down, with thecurrent airspeed in the middle. The samecolor scheme is used as on amechanical airspeed indicator torepresent the V speeds.

Digital Displays


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g p y

Attitude indicator There are twomodes for the attitude indicator,'Synthetic Vision' and 'Standard.' InStandard mode, an artificial horizon isshown as a white line, with blue for the

sky and brown for the ground. InSynthetic Vision mode, you'll see bluefor the sky, but will see arepresentation of terrain on the ground

including mountains, rivers and lakes.Terrain at or above your altitude isshown in red. What you see is asimulated view out the front window.

Digital Air SpeedsI di ti


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Indications Indicated airspeed in knots is shown as a

moving tape on the left side of the attitude box.The current digital airspeed is found in the boxin the middle of the tape. Colored arcs aredepicted on the tape as well as Vx and Vyspeeds for reference.

True Air Speed as calculated using thecurrent outside air temperature is shown at thetop of the screen.

Ground Speed is displayed at the bottom ofthe screen, as calculated using the GPS

A magenta airspeed trend line appears to theright of the airspeed tape, showing you whereyour airspeed will be in 10 seconds if thecurrent rate of change remains constant. Thisreally helps nail those approaches.

Di it l I di ti


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Digital Indications

Magnetic Heading isdisplayed in the boxat the top center ofthe display. The

heading isdetermined by asensitivemagnetometer andflies like a gyro. No

drift, no lag, and itdoesn't needresetting.

Digital Indications


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Digital Indications

Altimeter On the right side of the AI, analtitude tape displays the current altitudecalibrated up to 30,000. A foot is shown in

brown to indicate the ground level at yourcurrent position. This is derived from the

terrain database. Your altitude AGL is alsoshown at the bottom of the display.

The current altimeter setting is shown at thetop of the screen, and can be shown in Mb,MSL, or In. Hg. The setting is changed in the

settings screen. An Altitude 'bug' can be shown on the altitude

tape to help you remember an assignedaltitude, decision height, or whatever.

Digital Indications


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Digital Indications

Vertical speed indicator A blackbar to the left of the altimeter showsyour climb or descent rate along with

the digital value to the nearest 100feet/minute.

A magenta trend line will also showyou where your altitude will be in 10seconds if the current rate ismaintained. It it much more sensitivethan the VSI.


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Di it l I di ti


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Digital Indications

Slip/Skidindicator Atraditional ball in

the tube ofkerosene isdisplayed at thebottom of theattitude indicator,

as calculatedfrom the internalsensors.

Di it l I di ti


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Digital Indications

G-Meter - Itsalways nice toknow how many

Gs you're pulling,so we showyou. Min andMax Gs areshown in the

settings screen.


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Problems


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Problems Icing is a problem for pitot tubes when the air

temperature is below freezing and visiblemoisture is present in the atmosphere, as whenflying through cloud or precipitation. Electricallyheated pitot tubes are used to prevent iceforming over the tube.

The airspeed indicator and altimeter will berendered inoperative by blockage in the static

system. To avoid this problem, most aircraft intended for

use in instrument meteorological conditions areequipped with an alternate source of staticpressure.

In unpressurised aircraft, the alternate static

source is usually achieved by opening the staticpressure system to the air in the cabin. This isless accurate, but is still workable. In pressurisedaircraft, the alternate static source is a secondset of static ports on the skin of the aircraft, but ata different location to the primary source.


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The Lift Reserve Indicator (LRI) has beenproposed as an alternative or backup to theAirspeed Indicator (ASI) during critical stages offlight. This is an elegant device but is rarely foundin light aircraft or even transport jets. The

conventional Airspeed Indicator is less sensitiveand less accurate as airspeed diminishes, thusproviding less reliable information to the pilot asthe aircraft slows towards the stall. The actualstall speed of an aircraft also varies with flightconditions, particularly changes in gross weightand wing loading during maneuvers. The ASI

does not show the pilot directly how the stall isbeing approached during these maneuvers,whereas the LRI does.


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The LRI uses a three zone, red-white-greendisplay. During flight, the green zone is wellabove the stall where flight controls are firm,angle of attack is low, and the unused POWL ishigh. The white zone is near the stall where flightcontrols soften, angle of attack is high, and theunused POWL is diminished. The top of the redzone defines the beginning of the stall. Theseverity of stall increases as the needle travelsdeeper into the red. During the takeoff, the LRIuses dynamic pressure to operate and will not liftthe needle above the red zone until enoughairspeed energy is available to fly.


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The LRI has been well received by STOL pilotsand pilots of experimental or home-built aircraft.The LRI is very useful for short field landings,short field takeoffs, and slow speed maneuverssuch as steep turns, steep climbs, and steepdescents, and also allows pilots of fast or"slippery" aircraft to land with little or no float veryreliably. Since the LRI is so useful at the criticallower end of the flight envelope, most pilots willuse the LRI as a complement to the ASI, usingthe LRI for slow speed work and the ASI forcruising and navigational work.

Types of airspeedmeas rements


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measurements

Memory aid: "ICE-T" (iced tea), orIndicated->Calibrated->Equivalent->True. This is a Pretty Cool Drink,

giving you the errors compensatedfor between the speeds Position,Compression and Density


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At increased Density Altitude, for the same givenindicated airspeed the aircraft's true airspeed (TAS)will be higher, but the same indicated airspeed limits(IAS) apply. Likewise, most efficient cruise speed, totaldrag, available lift, stall speed, and other aerodynamicinformation depend on calibrated, not true airspeed.

Most aircraft exhibit a small difference between theairspeed actually shown on the instrument (indicatedairspeed, or IAS) and the speed the instrument shouldtheoretically show (calibrated airspeed or CAS). Thisdifference, called position error, is mainly due toinaccurate sensing of static pressure. It is usually notpossible to find a position for the static ports which, at

all angles of attack, accurately senses the atmosphericpressure at the altitude at which the aircraft is flying.


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The position of static ports must beselected carefully by an aircraftdesigner because position error

must be small at all speeds withinthe operating range of the aircraft.A calibration chart specific to thetype of aircraft is usually provided.


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At high speeds and altitudes, calibrated airspeedmust be further corrected for compressibility errorto give equivalent airspeed (EAS).Compressibility error arises because the impactpressure will cause the air to compress in thepitot tube. The calibration equation (seecalibrated airspeed) accounts for compressibility,but only at standard sea level pressure. At otheraltitudes compressibility error correction may beobtained from a chart. In practice compressibilityerror is negligible below about 3,000 m / 10,000feet and 100 m/s / 200 knots CAS.


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The true airspeed can be calculated as a functionof equivalent airspeed and local air density, (ortemperature and pressure altitude whichdetermine density). Some airspeed indicatorsincorporate a slide rule mechanism to performthis calculation. Otherwise, it can be performedwith a calculator such as the E6B handheldcircular slide rule. For a quick approximation ofTAS add 2% per 300m / 1000 feet of altitude toIAS (or CAS). e.g. IAS = 52 m/s /100 Knots. At3000 m / 10,000' Above Sea Level, TAS is 62m/s / 120 Knots.


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Questions?


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Altimeter


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flight instruments uni

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