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Instrument Approaches

Instrument Approaches
Instrument Approaches 

Objective: the student will be introduced to instrument approaches.

Completion Standards: the student will be able to explain the segment of an approach. The student will also be able to read an approach plate and practice briefings.

References: IFH, IPH, AIM, TERPS, Part 91.175, 91.187

Equipment: White Board and markers, iPad/ computer 

IP’s Actions:

  • Assess student

  • State the objective and completion standards

  • Writes down references

  • Provide attention getter

  • Present content

  • Assessment

  • Assign Homework

SP’s Actions:

  • Take notes

  • Ask Questions

Introduction: 

(Attention Getter) : (Link goes here)

Motivation: (Discuss purpose for lesson and relate to Attention getter)

Overview:

  1. Instrument Approach Segments

  2. Intro to the Approach Plate

  3. Types of Approaches

  4. Emergency ops

  5. Landing from Straight-In Approach

  6. Missed Approach

  7. Procedures For Instrument Approach

Content:




Purpose

To transition from the en route phase to landing


STARS (Standard Terminal Arrival Route)

  • To transition from an en route phase of flight to an instrument approach.

    • Like highways and exits

    • We may not use them

  • Altitude restriction’s

  • Speed restrictions

  • Example

    • TTHOR Three Arrival

    • If coming from higher altitudes

      • Atc may choose to vector

      • Can help clear up radios


Instrument Approach Segments

  1. Initial (IAF)

    1. To provide a method for aligning the aircraft for other segments

    2. IAF will be used on chart

    3. Examples

      1. Feeder routes

        1. Approach transitions from enroute phase of flight

        2. Depicted on IAP charts

      2. Terminal routes

        1. Are similar to feeder routes

        2. Originate at IAF where feeder routes terminate at the IAF

      3. DME Arcs

        1. Can be used as a transition

          1. But is part of an approach

      4. Course reversal

        1. Procedure turns

  2. Intermediate (IF)

    1. To provide a method for aligning the aircraft within 30 degrees of the final approach

  3. Final (FAF)

    1. Provides a path to the runway

      1. May be designated or not

      2. Guided by

        1. Precision approach

        2. Approach with vertical guidance

        3. Non-precision approach

  4. Missed Approach

    1. The go around point (MAP)

      1. Occurs at

        1. DA/DH

        2. MDA/ designated point


Intro to the Approach Plate

Go through an example approach plate

Sections:

  1. Briefing Section

  2. Plan View Section 

  3. Profile View Section 

  4. Approach Minimums Section 

  5. Runway Layout Diagram


The symbols in the Notes of the Briefing Section have the following associated meanings: 

  • T = Indicates Airport has Non-Standard Takeoff Minimums 

  • A = Indicates this Approach has Non-Standard Alternate Minimums


  • Examples of IAF fixes and also the procedures to go inbound (straight in/procedure turn)

  • Explain thoroughly on FAF (lightning bolt, Maltese cross)

  • TERPs

  • Plan view is where you grill procedure turns

  • Same goes with MAP (DA, MDA)


Types of Approaches:

Non-Precision Approach

  • Lateral guidance

  • Types

    • LOC (KDAB ILS 7L)

    • LOC BC (KMLB LOC BC 27L)

    • VOR (KMLB VOR 9R)

    • TACAN

    • LNAV

      • RNAV(KDAB RNAV 7L)

    • LP (GPS- WAAS)

    • NDB

    • ASR

When to start decent?

TERPS Diagram

OR

Ground speed X 5


OR

Ground Speed / 2 add 0



OR

  1. To determine the required rate of descent for a non-precision approach:

    1. Subtract the Touchdown Zone Elevation (TDZE) from the Final Approach Fix (FAF) altitude,

    2. Divide the result by the time inbound.

EXAMPLE

If the FAF altitude is 2000’ MSL, the TDZE is 400’ MSL, and the estimated time inbound is two (2) minutes, then a rate of descent of 800 FPM should be used [(2000-400)/2 = 800].

  1. To verify the position from which a descent from MDA (on a 3° glide path) to a landing on the intended runway can be made:

    1. Subtract the TDZE from the MDA,

    2. Divide the result by 300.

EXAMPLE

With an MDA of 800’ MSL and a TDZE of 400’ MSL, the position from which a descent from MDA to a landing should be initiated is approximately 1.3 nm from the threshold [(800-400)/300 = 1.3]

NOTE 

The runway threshold should be crossed at a nominal height of 50’ above the TDZE.


What About if there is no FAF

Use 10/10 Clear

  1. Within 10 NM

  2. Within 10 degrees oof final approach course

  3. Cleared for the approach 


DA VS MDA

For instrument approaches, there are 2 types of minimum altitudes:

  1. DA (Decision Altitude): Used on Precision Approaches

    1. DH = Decision Height – Same as DA but given in AGL

  2. MDA (Minimum Descent Altitude): Used on Non-Precision Approaches

    1. MDH = Minimum Descent Height – Same as MDA but given in AGL.


VISUAL DESCENT POINT (KMLB/ VRB VOR)

  • VDP stands for “Visual Descent Point.” 

  • At this point, the pilot will make the decision to either continue to landing or to execute the Missed Approach Procedure. 

    • However, the pilot cannot begin the Missed Approach Procedure until reaching the Missed Approach Point. VDP’s are only applicable for non-precision approaches.

  • If there is no VDP depicted, we can figure our VDP by taking our Height Above Touchdown (HAT) and dividing it by 300 to get a distance in NM.


Precision approach

  • Vertical and lateral guidance

  • Meets standards of ICAO annex 10

  • Types

    • PAR

    • ILS

    • GLS


DA VS MDA

For instrument approaches, there are 2 types of minimum altitudes:

  1. DA (Decision Altitude): Used on Precision Approaches

    1. DH = Decision Height – Same as DA but given in AGL

  2. MDA (Minimum Descent Altitude): Used on Non-Precision Approaches

    1. MDH = Minimum Descent Height – Same as MDA but given in AGL.



Approach with vertical guidance (AIM 1-1-18)

  • Vertical and lateral guidance 

    • WAAS

  • Is not required to meet the standards of ICAO annex 10

    • ICAO Annex 6

  • Types

    • Baro-VNAV

    • LDA with glidepath

    • LNAV/VNAV (RNAV)

      • Uses WAAS to eliminate errors that can be introduced by using barometric altimetry

    • LPV (RNAV)


Visual and contact approaches

To expedite traffic, ATC may clear pilots for a visual approach in lieu of the published procedure

Visual Approach

  • A visual approach is an ATC authorization for an aircraft on an IFR flight plan to proceed visually to the airport of intended landing

  • Pilots must remain clear of clouds at all times


Contact approaches

  • A contact approach cannot be initiated by ATC

  • To expedite arrival, as long as the airport has a SIAP the reported ground visibility is at least 1 SM, and pilots are able to remain clear of clouds with at least one statute mile flight visibility throughout the approach.


Circle Approach (AIM 5-4-20)

  • Circling Minimums are established so pilots can fly an approach to a particular runway but then land on another runway. 

    • Take this example, our pilot executes an Instrument Approach to Runway 9 but the winds at the airport are reporting 270 @ 15 knots. The pilot can execute the approach for Runway 9 and then circle to land on Runway 27, which is favorable for the current wind conditions.

  • The circling minimums published on the instrument approach chart provide a minimum of 300 feet of obstacle clearance in the circling area

    • Chart Below

  • The pilot should maintain visual contact with the runway of intended landing and fly no lower than the circling minimums until positioned to make a final descent for a landing






Emergency ops/Faults

What to do if you lose glideslope during an ILS approach?

  1. Discontinue the decent and go missed

    1. Advise ATC

  2. Use non precision minimums

    1. Localizer minimums

What to do if a loss of primary flight instruments occurs?

  1. Primary flight instruments

    1. AHRS

    2. ADC

  2. Radios are operational

    1. LOC

    2. VOR

    3. GPS

  3. Adapt scan

    1. Secondary/ standby instruments

    2. Subtle movements goes along way

  4. Declare an emergency

    1. 91.187


Landing From Straight-In Approach (IF 91.175 Is Met)

Transition to visual

  • Effect of specific environmental, operational, and meteorological factors.

  • Transition to, and maintenance of, a visual flight condition.

  • Adherence to ATC advisories, such as NOTAMs, wind shear, wake turbulence, runway surface, and braking conditions.

  • Completion of appropriate checklist items.

  • Maintenance of positive aircraft control.


Common Errors

  • Inappropriate division of attention during the transition from instrument to visual flight conditions. 

  • Failure to complete required checklist items. 

  • Failure to properly plan and perform the turn to final approach. 

  • Improper technique for wind shear, wake turbulence, and crosswind. 

  • Failure to maintain positive aircraft control throughout the complete landing maneuver


Missed Approach

PURPOSE OF THE MANEUVER

Missed Approaches should be initiated anytime the Instrument Landing Criteria of FAR 91.175(c) is not met.


Precision Approaches

When performing a Precision Approach Procedure, the Missed Approach will be initiated upon arrival at the DA/DH.


Non-Precision Approaches

When performing a Non-Precision Approach Procedure, the Missed Approach will be initiated upon arrival at the Missed Approach Point (MAP).


DA VS MDA

For instrument approaches, there are 2 types of minimum altitudes:

  1. DA (Decision Altitude): Used on Precision Approaches

    1. DH = Decision Height – Same as DA but given in AGL

  2. MDA (Minimum Descent Altitude): Used on Non-Precision Approaches

    1. MDH = Minimum Descent Height – Same as MDA but given in AGL.


CIRCLING TO LAND (AIM 5-4-21)

  • Circling Minimums are established so pilots can fly an approach to a particular runway but then land on another runway.

  • If sight of the runway is lost during the circle to land, the pilot should initiate a climbing turn toward the runway to join the missed approach procedure.



DESCENDING BELOW DA OR MDA

  1. The aircraft is in a position to make a safe landing using normal descent rates and maneuvers.

  2. The flight visibility is not less than what is prescribed on the Instrument Approach Chart.

  3. The pilot must have one of the following in sight: (Part 91.175) (AIM 2-1-1| 2-1-6)

    1. The Threshold

    2. The Threshold Paint

    3. The Threshold Lights

    4. The Touchdown Zone

    5. The Touchdown Paint

    6. The Touchdown Lights

    7. The Runway

    8. The Runway Paint

    9. The Runway Lights

    10. Runway End Identifier Lights (REILs)

    11. Visual Glideslope Indicator (VGSI)

    12. Approach Light System (ALS)


Note: If the pilot sees only the Approach Light System, he/she may descend to 100’ above the Touchdown Zone Elevation (TDZE). At which point, the pilot must see one of the other items above OR the red terminating side row bars on the approach light system in order to continue to land. If the pilot descends to 100’ above the Touchdown Zone Elevation (TDZE) and does not see one of the other criteria listed above, then he/she must immediately execute the published Missed Approach Procedure.


THE INSTRUMENT APPROACH PLATE

The instructions for the missed approach procedure are usually located in 2 different places on the instrument approach plate. 

  1. In the Briefing Section you can find the full missed approach instructions in textual format. 

  2. In the Profile View Section you can find a pictorial diagram of the missed approach procedure.

Alternate Missed Approach Holding Fix

Some instrument approaches also include an alternate missed approach holding fix. If ATC deems necessary, they can direct the pilot to proceed to the alternate holding fix (instead of the normal one). This can be done for safety and in situations of high traffic.


VISUAL DESCENT POINT

VDP stands for “Visual Descent Point.” 

  • At this point, the pilot will make the decision to either continue to landing or to execute the Missed Approach Procedure. 

  • However, the pilot cannot begin the Missed Approach Procedure until reaching the Missed Approach Point. 

    • VDP’s are only applicable for non-precision approaches. Hence, the “LOC Only” symbol seen on the chart does not apply if flying the approach as an ILS Approach.


APPROACH CATERGORIES

In this situation, a pilot can figure his/her approach speed by taking the aircraft’s Vso (stall speed) and multiply it by 1.3. Once the pilot knows his/her aircraft’s approach speed, he/she can also know which approach category they fall in by adhering to the approach category numbers below. 


How to go missed

Use the 5 C’s

  1. Climb: Pitch for VX or VY

  2. Cram: Full power (smoothly)

  3. Clean: Flaps and gear UP

  4. Call: Make a radio call

  5. Checklist: Climb checklist


Procedures For Instrument Approach

WIRED (Checklist)

  1. Weather

    • ATIS

  2. Instruments

    • Approach Briefing

  3. Radios

    • Configure approach

    • Navigation

  4. Environment

  5. Descent

    • Checklist


Choosing Minimums

  • Approach categories (Previous section)

  • 1.3 X VSO

    • We fly at 100 KN

      • To expedite traffic

    • Approach speed is 65 KN



Example ATC Instructions for Approach

  1. Radar vectors for approach

  2. Expect full approach

  3. Cleared for the Approach

    1. Distance

      1. Direct to a point then cleared

    2. Altitude

      1. Altitude until a point then cleared for the approach

    3. Once established on LOC the cleared 

Cleared Now What?

Call outs

  • Prior to Final Approach

    • CDI Alive

  • Prior to intercepting a glide slope

    • Glide slope alive

AT final approach

  1. At the FAF (glideslope intercept), call out, “Final approach fix. ”Set power to 2000 RPM. Then call out, “(Current airspeed) knots, flaps 10.”Set the flaps to 10°. Adjust pitch to 1° down to maintain glideslope and 100 KIAS.

NOTE To determine an approximate rate of descent to maintain the glideslope, divide groundspeed by 2, and then multiply the result by 10 (e.g., 90 knots/2= 45, 45 x 10 = 450 fpm).

  1. At 500’ above DA(H), call out, “500.” Complete the BEFORE LANDING FLOW.

  2. At 100’ above DA(H), call out, “100.”

  3. At DA(H), call out, “Minimums.”

  4. Continue the descent when:

  1. At least one visual reference for the intended runway is distinctly visible and identifiable, and the flight visibility is not less than prescribed in the standard instrument approach being used. Call out, “Continuing.”

  1. NOTE Descend no lower than 100 above touchdown zone elevation when referencing the approach light system without seeing the red terminating bars or red side-row bars.

  1. With the runway in sight and in a position from which a descent to a landing on the intended runway can be made at a normal rate of descent using normal maneuvers, reduce power as required for landing. At or below VFE(full)(85 KIAS), call out,“(Current airspeed) knots, flaps full. ”Set the flaps to full for landing.

NOTE Maintain the localizer and glideslope during the visual descent to a point over the runway where the glideslope must be abandoned to accomplish a normal landing.

  1. If no visual reference is in sight at DA(H), or visual reference is lost when continuing the descent from DA(H), call out, “Going missed. ”Execute a MISSED APPROACH PROCEDURE(see page 2-146), complying with the published missed approach procedure, or as directed by ATC.




Conclusion

  1. Instrument Approach Segments

  2. Intro to the Approach Plate

  3. Types of Approaches

  4. Emergency ops

  5. Landing from Straight-In Approach

  6. Missed Approach

  7. Procedures For Instrument Approach

(Questions to assess student)

What are the segment of an approach?

How to read approach plate?

What is the difference between a DA and MDA

When do we go missed on VOR MLB approach

What are the 5 C’s


HW: Look through approach plates and practice briefing!


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