Killers In Aviation

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Killers In Aviation
Controlled Flight Into terrain Non-Precision
Approach Is The Major Cause Of CFIT
Barometric VNAV Approach
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Assumptions Made

• That You Have Read The 1 In 60 Rule Paper I
  Wrote
• That You Have Learnt How To
• Determine Descent/Climb Gradient
• Determine Rate Of Descent/Climb Based On Gradient
  IAS
• Spot Unusual Non-Precision Approaches
• If Not, Do So As Soon As Possible!

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Accident Statistics
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Non Precision Approach
The Classic Dive Drive Or Step Descent
Non-Precision Approach Has Been Singled Out As
The Major Cause Of CFIT By ICAO, FAA FSF.
Examples

• Flying Tigers B747-200 Flt 66 Freighter In KL
  (18.2.1989)
• Air Inter A320 Flt 148 In Strasbourg (20.1.1992)
• PIA A300 Flt PK 268 In Kathmandu (28.9.1992)
• USAF CT-43A (B737) In Dubrovnik Croatia
  (03.04.1996)
• SIA L31 LearJet Trainer In Ranong (25.7.1997)
• Korean Air B747-300 Flt 801 In Guam (7.8.1997)
• Gulf Air A320 Flt GF072 In Bahrain (23.8.2000)
• CrossAir Avro RJ100 Flight 3597 In Zurich
  (24.11.2001)
• And More! Many more!

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Precision NP Approach StatisticsSurvey Between
1984-1993
Risk Ratio Between NPA PA Is 5.21
Reference Killers In Aviation Flight Safety
Foundation
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SOLUTIONS

• Fly Precision Approach Whenever Possible (ILS)
• Constant Angle Non-Precision App
• Barometric VNAV Approach (FMS)
• In The Near Future
• Wide Area Augmentation System (WAAS)
• Local Area Augmentation System (LAAS)

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Step Down Non Precision ApproachMain
Disadvantage Non Stabilised Approach

• The Major Cause Of CFIT During Approach Landing
  

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A Typical Low Angle NPA

• Example Of A Close-Call CFIT Incident

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Constant Angle Non Precision ApproachMain
Advantage Stabilsed Approach
Can Be Done With LNAV-V/S But Best With LNAV/VNAV

• It Is An Angle Projected From TCH (50ft)
  Backwards To FAF It Is Normally A 3 Slope (Up
  To 3.77)

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Stabilsed Approach - FSF

• Aircraft On Correct Flight Path
• Only Small Heading/Pitch Changes To Stay On Path
• Speed No Less Than Vref No More Than Vref20kt
• Aircraft In Correct Landing Configuration
• Sink Rate No More Than 1000fpm
• Correct Power Setting
• Flying Within Limits CAT 1, CAT 2 Circling
• All Briefings Checklists Conducted
• Special Briefings Required For Unique Approaches
  Non-Normal Situation
• An approach that becomes unstabilised below
  1000ft above airport elevation in IMC or below
  500ft in VMC requires an immediate go-around

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Unstabilised Approached - FSF

• High Fast Excessive Rate Of Descent
• Shallow Approach Below The Glide path
• GPWS Warning
• Mode 1 Sink Rate
• Mode 2A Terrain (Less Than Full Flaps)
• Mode 2B Terrain (Full Flaps)
• Final Approach Course Intercept Too Close
• Lateral Unstabilised Final Approach Failure To
  Correct For Crosswind Component
• Excessive Bank Angle For Final Maneuver
• Unstabilised Approach With Late Or No
  Go-Around Decision
• Inadvertent Descent Below Glide Path

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Precision Non Precision Approach

• ILS Is A Precision Approach.
• Guidance Signals Are Transmitted From The Ground.
  They Are Not Easily Affected By Weather
  Conditions.

• Barometric VNAV Is Still A Non-Precision App.
• It Is Vertical Path Angle, Two Points In Space
  Calculated Backwards By The FMS/GPS From TCH (Or
  From Missed-Approached Point) Backwards To The
  FAF.

WAAS LAAS? Discuss Later
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GPS Made It All Possible

• Originally Developed For Military Use Called
  NAVStar - NAVigation System by timing and ranging
• Constellation Of 24 Satellites Orbiting In 6
  Planes
• Selective Availability (SA) P Code C/A
  Code It Was Turned Off In May 2000.
• Class C Aircraft - FMS/GPS RAIM VDI Equipped
• RNAV 0.3NM Compliant (But lt0.14NM In Practice)
• Made Lateral/Vertical Navigation Possible Now
• Differential GPS Ready (WAAS/LAAS) Very Soon
• Replacing ILS May Be Sole Mean Of Precision
  Navigation Landing System In The Near Future

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Barometric Vertical Navigation(BAROMETRIC VNAV)

• A navigational system which presents computed
  vertical guidance to the pilot referenced to a
  specified Vertical Path Angle (VPA).
• The computer resolved vertical guidance is based
  on barometric altitude and is either computed as
  a geometric path between two waypoints or an
  angle from a single waypoint.

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FMS Computed Vertical Descent Path
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Barometric VNAV ApproachFAA Approved FMS/GPS
Equipped A/C
Examples RNAV (GPS), VOR, NDB, LCTR, Loc B/C etc

• Title 14 Code of Federal Regulations (14 CFR) -
  
• FAR Parts 121, 125, 135, or 129.
• FMS/GPS VNAV System Certified i.a.w. AC 20-129.
  
• (e.g. B747-400, B777-200/300, A340 RNAV)
• GPS Is RAIM Receiver Autonomous Integrity
  Monitoring
• FMS Database is ARINC 424 Compliant (Intl
  standard)
• Airport Is VNAV Approach WGS-84 Compliant
  (Surveyed)

Reference Joint Flight Standards Handbook
Bulletin for Air Transportation (HBAT) Vertical
Navigation (VNAV) Approach Procedures Using
DA(H) OpSpec C073 13 Jul 99
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Required Obstacle Clearance

• At IAF 1000ft
• At IF 500ft
• At FAF 250ft
• If No FAF 300ft
• (Reference ICAO Pans Ops Volume 1 2)

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Terminal Approach Area

• IAF Is over the facility (e.g. In a hold)
• IF Begins at completion of procedure turn
• FAF Is when flying over the facility to land

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Approach Segment Obstacle Clearance
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Obstacle Protected Surface (71Slope)(Within 1nm
From FAF)

• If The Obstacle Has A Base Of 1nm From FAF,
• The Obstacle Would Be 868ft In Height

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Advantages Of VNAV Approach

• Stabilised Approach
• No Drastic Change In Power, Speed Attitude
• Correct Rate Of Descent 750 to 1000fpm
• Descent Angle Between 2.75 3.77
• Need Not Hug The Ground
• Ready To Land When Visual With Runway
• Familiar Visual Perception As ILS Approach
• Go-Around At DA(H)
• Less Prone To CFIT Of Course!
• Do Not Level Off At MDA And Drive To MAP!
• This Defeats The Whole Purpose Of CANPA.

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Definitions Of DA(H) MDA

• MDA The lowest to which descent shall be
  authorised in procedures not using a glideslope.
  Aircraft are not authorised to descend below the
  MDA until the runway environment is in sight and
  the aircraft is in a position to descend for a
  normal landing.
• DA In an approach with vertical guidance, DA is
  a specified altitude in mean sea level at which a
  missed approach must be initiated if the required
  visual references to continue the approach have
  not been established.

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Changing MDA To DA(H)

• Some Operators (e.g. SIA) Chose To Add 50ft To
  MDA To Prevent Busting The Altitude During
  Go-Around
• MDA 50ft Becomes DA(H) When A Constant Angle
  Final Approach Is Used
• Drive From DA/H To MAP Is Inappropriate
  Dangerous
• Some US Airports Have Authorised VNAV DA(H),
  Which Is Lower Than MDA Not Necessary To Add
  50ft To It.
• When WAAS Is Fully Operational (Discuss Later)

No Drive In To MAP From DA(H)!
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Go-Around At DA(H)

• When the use of VNAV path guidance is
  incorporated into the approved training program
  and a VNAV path is used to fly eligible
  procedures with a DA(H),
• .. a slight momentary descent below the published
  DA(H) is considered to be acceptable while
  arresting the descent during the initiation of a
  missed approach which has been initiated at or
  above the specified DA(H)

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LNAV Approach (Has Vertical Guidance But With No
Published DA(H))

• Necessary To Add 50ft To MDA To Turn It To DA(H)

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VNAV (With Vertical Guidance And DA(H) Published)

• Authorisation Required To Use VNAV DA(H)
• No Need To Add 50ft To The DA(H)

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Effects Of Cold Temperature For Sea-Level Airports

• A/C Altitude Is Correct Only In ISA Condition
  (15ºC)
• A/C Altitude Is Higher Than Actual In Hot Weather
  Condition (45ºC)
• A/C Altitude Is Lower Than Actual In Cold Weather
  Condition (-15ºC)

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VPA Deviations For Sea-Level Airports
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Cold Temperature Correction Table

• Tips
• During Deep Freeze Winter Operations To Stations
  Like PANC, KORD Or KJFK
• Prepare Early Preferably During Cruise. Check
  NOTAM, TAF METAR For Expected Runway In Use
• If LNAV/VNAV Approach Is Expected, Work Out The
  Temperature Corrections And Note Them Down In
  Pencil On Relevant The Jeppesen Chart
• For B777 Crew, Study The Russian En-Route
  Airports Carefully And Work Out The Cold
  Temperature Corrections (e.g. Magadan)
• Use Only With Prior ATC Co-Ordination

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Cold Temperature Correction

• VNAV Not Authorised Below -25C
• GPS or RNP 0.3 Required
• DME-DME RNP 0.3 Not Authorised
• WAAS VNAV Not Authorised (Discuss Later)
• VGSI Not Co-Incident

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Cold Temperature Correction

• Do Not Add Or Delete Any Waypoint After The FAF
  Onwards.
• You May Modify The Altitude Of The FAF For Cold
  Temperature Correction Purpose.
• FMS Will Continue To Fly The VNAV Path, The
  Higher Of The GP Angle And The Modified Altitude.

Source Boeing Mr. Bill Royce
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Australian CAA (ICAO Compliant)

• Procedure Altitude Recommended Crossing
  Altitude
• Segment Minimum Safe Altitude Its A Hard
  Altitude

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US FAA TERPS CriteriaAnd ICAO Requirements
Qualification or Proficiency Checks

• For flight training and proficiency checking
  purposes, if applicable, a flight technical error
  (FTE) or pilot deviation from the desired
  vertical track, of 100/-50 feet is considered
  acceptable for adherence to the depicted VNAV
  path.

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Flight Crew Should Be Familiar With The
Barometric VNAV Procedures

• Actions At DA(H)
• VNAV Path Mode Selection
• Remote Altimeter Setting Restriction
• Charting
• Non-Standard Temperature Effects On Barometric
  VNAV
• VNAV Failure Modes Mode Reversion

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Setting Of Go-Around Altitude

• Final Approach Using VNAV
• As Soon As The Airplane Is At Least 300ft Below
  The Missed Approach Altitude And Stabilised On
  Final Approach in VNAV PTH, Set The MCP Altitude
  To The Missed Approach Altitude (B744 FCTM Page
  4.45)
• Final Approach Using LNAV V/S Mode
• Approximately 300ft Above The MDA, Select The
  Missed Approach Altitude. (FCTM Page 4.49)

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Halifax Loc Back Course Rwy 33

• Barometric VNAV Can Also Be Used For Loc BC
  Approach

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Disadvantages Of VNAV Approach
FMS Software Codes Can Be Erroneous

• Effects Of Temperature On Barometric VNAV
  Approach Is Still Not Fully Appreciated By Many
  Pilots
• Special Training Practice Are Essential To Stay
  Current
• GPS Signals Are Weak And Can Subject To Natural
  Interference Or Deliberate Sabotage
• FMS VNAV Functions, Modes FMA Annunciations Can
  Still Be Confusing And Continue To Surprise
  Many Pilots
• In VNAV Mode, Premature Level Off May Occur
• FMC Cruise Speeds May Not Comply With
  Speed/Altitude Restrictions

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A Survey Of VNAV Function Issue And Surprising
VNAV Behaviors
Ref Joint Study By RAND/Honeywell, Boeing NASA
UOC.
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The Future Is Here! (Almost)Commissioned On 10th
July 2003On Trial Now Fully Operational 2005
- 2009

• WAAS Is A CAT 1 Precision Approach

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LAAS GLS The Future Is Here

• GLS IS CAT 1, 2 3 Capable
• It is A Precision Approach
• Local Area Augmentation System - LAAS
• Known As SBAS In Europe

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Local Area Augmentation System

• LAAS Is CAT I, II III Capable (GBAS In Europe)
• Planned To Replace ILS In The Near Future In USA

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Flight Deck Display Controls
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Precision Approach With No ILS!
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System Accuracy
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Suggested Readings

• Joint Flight Standards Handbook Bulletin for Air
  Transportation (HBAT)
• FAA AC 90-97 Use Of Barometric VNAV For
  Instrument Approach Using DA(H)
• QA For RNAV VOR NP Approaches (US Airways)
• FAA AC 120-29A Criteria For Approval Of
  Non-Precision, CAT 1/2 Wx Minima For T/O, App
  Landing.
• Non-Precision Instrument Approach Procedure
  Design Philosophy Obstacle Clearance Panel
  ICAO
• CASA CAAP 178-1 (0) Non-Precision Approaches
• B744 FCTM Page 4.33 to 4.52 (Plus Ops Policy)
• Jeppesen Series Clinic All 32 Chapters
• All The Documents Are Available In The CD-Rom

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A Special Tribute To Jim Terpstra
Senior Corporate Vice President Jeppesen
Sanderson, Inc.
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Thank You For Your Patience!

• This Has Been A Presentation By The
• Technical Committee Of ALPAS
• Prepared By Capt Eddie Foo S N
• For More Information On Barometric
• VNAV Approach, Get A Copy Of The
• CD-Rom Or E-Mail..
• eddiefoo_at_starhub.net.sg

25th January 2005