IFR Taxi Checks Instrument Scan IFR Instrument Taxi

IFR Taxi Checks & Instrument Scan

IFR Instrument Taxi Check Ø Magnetic Compass: Full of fluid, known headings, swinging freely, left turn- #’s decreasing, right turn #’s increasing Ø Airspeed Indicator: zero Ø Attitude Indicator: erect and stable in 5 min. , no more than 5º bank during turns Ø Altimeter: +/- 75 feet from field elevation (not a limitation)

IFR Instrument Taxi Check (continued) Ø Turn Coordinator: “Ball outside, airplane inside” of turn Ø Heading Indicator: correct heading, left turn#’s decreasing, right turn #’s increasing Ø Vertical Speed Indicator: note current indication for zero (not required for IFR) Ø Alternate Static Source: check

Instrument Flying Fundamentals 3 Skills: (“SIC”) �Cross-Check (Scan) �Interpretation �Aircraft Control

Cross-Check (scanning) Attitude Indicator Single most important instrument � supplies most information at 1 glance � It gives immediate information on both pitch and bank � Scan centers on this instrument most of the time Used during transitions

Types of Scans � Basic T � Circular � Radial � Inverted V

Basic T Scan � � Used during normal flight Only works with a standard panel layout

Circular Scan � Use during partial panel situations � includes a bank instrument every couple of instruments (compass and turn coordinator)

Radial Scan � � Centered on AI Used during transition from one condition to another (i. e. , climb to cruise)

Inverted V � � Used when instruments are conflicting Uses 3 different instruments, 3 systems Two instruments should agree; 3 rd is faulty May have to look at another instrument to verify failure

Other Scan Items Include engine instruments, navigation , GPS instrument, etc. , every 2 or 3 scans Beware of scan errors. . .

Scanning Errors v Fixation v Omission v Emphasis

Fixation o o Staring at a single instrument Sometimes necessary May result when student is weak on other fundamentals EX: staring at altimeter while approaching minimums, heading wanders

Omission o o Most likely with other instruments; Navigation or Engine Excluding 1 or more instruments from scan Possibly caused by not anticipating instrument indications following attitude change Ex. : rolling out of 180º steep turn & establishing straight & level with AI (AI precesses)

Emphasis o o o Inappropriate reliance on 1 specific instrument Not as bad as fixation, because scan is still maintained Ex. : Trying to hold altitude using attitude indicator alone

Instrument Interpretation Requires understanding of instruments operating characteristics (VSI lag, HI precession, etc. ) Instrument grouping: 2 schools of thought Primary and Secondary Control and Performance

Primary and Secondary Instruments Primary instruments - provide most essential information for specific situation values assigned (ex. : fly hdg 270º - HI primary) Secondary instruments - help maintain desired indications on primary instruments (ex: turn coordinator, magnetic compass) Divides instrument panel into pitch, bank, and power instruments Attitude Indicator: The only time it is primary is during transitions

Pitch Control

Bank Control

Power Control • Depends if airspeed or power setting is assigned

Control and Performance Dividing instruments into 3 groups Control instruments: show instantaneous airplane performance Performance instruments: direct value can be assigned Navigation: show’s airplane’s position relative to the earth

Control and Performance (continued) � � � Good to use in high performance airplanes �military uses it a lot Use radial scan �attitude indicator to performance instrument �performance instrument back to AI �etc…. “Pitch + Power = Performance”

Instrument Flight Process v “Pitch, Power, Trim” and v “CCHAT” v C: Change v C: Check v A: Adjust v T: Trim

Tips and Rules of Thumb � Avoid “death grip” on yolk � lead roll in/out by 1/2 bank angle � lead level off by 10% of climb rate � Under power / over power airspeed transitions

Partial Panel IR Flight � � � Definition: loss of at least 1 instrument �most common situation: no AI and HI �failure can be single instrument or entire system Need to use Timed Turns &/or Compass turns to accurately fly headings Especially important: �smooth aircraft control �allow time for instruments to stabilize

IR Unusual Attitude Recovery � � Definition: any airplane attitude not normally required (or desired) for instrument flight Some causes: �turbulence �disorientation �instrument failures �lack of proficiency

IR Unusual Attitude Recovery (continued) Nose high condition

IR Unusual Attitude Recovery (continued) v Nose high recovery procedure üincrease power ülower nose to level attitude ülevel wings ürestore power when airspeed returns to normal

IR Unusual Attitude Recovery (continued) Nose low condition

IR Unusual Attitude Recovery (continued) v Nose low recovery procedure üreduce power ülevel wings üincrease pitch attitude to level ürestore power when airspeed returns to normal

Partial Panel IR Unusual Attitude Recovery q q q Use Turn Coordinator to roll wings level Use pitot/static instruments to determine climb or descent Level pitch attitude - pitot/static reversal qhold elevator pressure at this point to maintain level flight