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The best way to study this material is having several IFR charts available to help find an actual situation in your area for analysis. Do three charts per session.

VFR-on-top (OTP)
Filing and getting a clearance makes you IFR. OTP is a mix of IFR/VFR that reduces separation standards. Compliance with VFR visibility and cloud clearance is required along with IFR minimum altitudes. (FAR 91.177) Under IFR to IFR standards terminal areas require 3 miles lateral and 5 miles in center airspace. IN OTP the pilot must fly cleared routes but can request direct and get it off airways with radar while maintaining VFR altitudes and clearances.

OTP does not require clouds to be flown. Without radar you will not be allowed to fly below MEA or higher. An OTP aircraft can avoid the climbs and vectors required for IFR separation. OTP can be filed for and obtained after completing the DP requirements. Under OTP you can climb to any altitude below 18,000' that is above the instrument minimums so long as you make required reports to ATC regarding the changes.

--Adhere to VFR cloud separation
--Climb and descend at will
--No need to fly assigned route

You must know where the DME is located when flying an ILS. Don't leave a navaid during an approach that has DME if it can be avoided.
--Threshold crossing height (TCH) should be added to the threshold elevation for altimeter reading. Do not use TDZE (Touchdown zone elevation)
--Over 90% of missed approach accidents occur on the second missed.
--ATC cannot give a visual approach when visibility is less than three miles. In Class D airspace the ceiling must be better than a thousand feet.
--To get a contact approach the aircraft must be on an IFR flight plan. A contact requires one-mile ground visibility and an instrument approach to the airport. A contact approach is the IFR equivalent of a SVFR approach.
--When you are unable to interpret a clearance, come up with an alternative suggestion to ATC.
--Avoid procedure turns where you can.
--A non-radar approach must begin at a charted initial approach fix. ( IAF)
--The last chance you have to check your altimeter is when crossing the non-precision FAF.
--If your glide slope indicator needle is acting funny, it is best to consider it unreliable and change to non-precision minimums IF you have not already descended lower. If lower, a missed is your only option.
--For the PTS an aircraft must be able to perform at least two of the non-precision approaches and one precision approach. An ADF is not required. Marker beacons are required but can be ‘called' by RADAR..
--Light IFR aircraft should have standby vacuum system or pump.
--There is no evidence that engine problems are more likely to happen at night or that night weather is any worse than day weather.
--Only a small percentage of total IFR flying occurs at night yet over half of the IFR accidents occur at night.
--Variations of transitions, segments and fixes make approaches.
--The simplest approach on an airport will have only a final segment, MDA and missed approach. No timing, no intermediate segment, intermediate fix or final fix. Visual descent point (VDP) may exist. There is no glide slope information. --Final approach may have several step down fixes.
--At a minimum descent altitude (MDA) level flight continues, usually by time, to the missed approach point.
--ATC cannot vector you to intercept the ILS above glide slope. But they do and have to me.
--Vectoring altitude is 1000' AGL in flat terrain and 1500/2000' AGL where mountainous.
--The "Maltese Cross" on approach plates is the final approach fix for non-precision approaches only.
--The final approach fix for precision approaches is glide slope interception.
--If the ILS becomes a localizer approach then the time over the Maltese Cross must be noted.
--Ground speed can be determined electronically by DME, LORAN or GPS more commonly by using the wind direction and velocity from whatever source.
--Use of the airport wind is very uncertain since wind speeds vary greatly with altitude. The variability of the approach ground speed along with other instrument factors are what makes most approaches non-precision.

Getting Vectors to the FAF
One initial approach procedure can be the use of radar as a substitute for any other published approach.
--The controller flies you a modified base entry and then gives you an intercept heading of 20 or 30 to the ‘approach gate'.
-- The approach gate is defined as a point at least one mile outside the fix and five miles from the runway.
--The radar intercept altitude must allow you to descend within the limits of the approach procedure.
--The normal intercept of a radar vector is within the intermediate segments.
--Only on an on-airport VOR or NDB can the radar vector intercept the final approach.
--The usual length of the intermediate segment is five miles except for shallow interceptions of an ILS.
--The ILS final approach fix is where the charted intermediate altitude intercepts the glide slope.
--Most ILS vectors must be at a higher altitude than would be a localizer approach for this reason.
--Once you descend below the last assigned altitude, you must be inside the one and one-half mile charted approach airspace of the procedure.

ATC Vector Strictures:
--2 miles outside the ‘gate' unless a visual approach.
--Unless ceiling 500' above MVA/MIA and 3 mile visibility or closer vector requested by pilot.
--ILS vector cannot be above the glide slope or below the fix altitude.
--Vector must allow published descent.
--ATC has cushion of additional 300' obstacle clearance for each mile over three beyond the FAF.
--ATC must give your position relative to a fix before clearing you for approach.

Pilot Vector Strictures
--Do not turn to intercept UNLESS given ATC clearance.
--You must maintain or be given an altitude before being cleared for the approach. 91.175(I)
--Strong winds can cause problems. Don't rely on ATC for wind correction
--Center vectors come from distant antenna and are unreliable. Same with BRITE in many towers.
--You can intercept final closer than 3 miles on request.
--Even though a course change follows the FAF your intermediate vector is considered to be a vector to final.
--A clearance to an approach fix is not equivalent to a radar vector to final.
--Pilot should reject a clearance and vector that gives you a straight in where a course reversal is part of the procedure.
--Where a VASI or PAPI serves as a glide path assistant some degree of obstacle clearance is assured as long as you don't go below the indicated center of the path.

Timing, whether you use a traditional or electronic timer makes no difference. Time is the second T of the 5/7 Ts. for every segment of the instrument approach. You may not use it every time but it should remain as part of the sequence. The time required for an approach depends on ground speed. The timing of an approach involves more than just noting the time off the chart. Since the time is based on ground speed we must factor into it the effect of the wind, our proficiency at holding an airspeed during established flight and transitions. The result of your timing efforts will only be as accurate as your data input.

The "Maltese Cross" on approach plates is the final approach fix for non-precision approaches only. An ILS should be timed passing the non-precision FAF (Maltese cross). This guarantees awareness if the glide slope fails and you need to continue with a localizer-only approach. The FAF for an ILS is the point you intercept the glide slope at the designated altitude on the chart. The localizer FAF may be inside or outside marker, begin descent at interception (See Livermore chart) The final approach fix for precision approaches is glide slope interception.

The greatest hazard associated with non-precision approaches is the descent from MDA to the runway. In relatively poor conditions the pilot must change from IFR to VFR flight. Your localizer is only good within three degrees of centerline. An LDA's precision is even less. It is not unusual to miss the runway by 1/2 mile at the MDA of a NDB approach.

Select a heading
Reference Heading is the heading that will keep the needle centered. Because of wind you must bracket this heading through referral to the Heading Indicator. One system uses 1/2 angle corrections of ever decreasing amounts. (see instructor)

Initial changes to find the reference heading should be 5 degrees. (10 degrees only if 1/2 deflection.) All turns by reference to heading indicator. Stabilize your heading and airspeed based on the wind. Use only rudder for heading changes of three degrees or less.

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