IFR Descents
Approach descents
--Must have clearance
--If confused about location, don’t descend. Climb for altitude.
--Must be on published route, or descend when: cleared for approach and on a published route.
--Do not descend flying direct to a fix unless on a published approach.
--Never make descent below DH or MDA unless you can see at least one of visual items required by FAR 91.175.

Clearance on Unpublished Route
--ATC gives minimum for crossing fix, or
--Maintain last assigned altitude
--MSA for emergencies only

Procedures
Procedure 1:
Gear down at FAF or downwind.
Procedure 2:
Gear and Flaps at initial descent from cruise. This allows early detection of gear/flap problems and allows
power to be retained to avoid shock cooling.

Cautions
We usually have a single engine, electrical source, and vacuum pump. There is nothing in the FARs that require dual systems but many pilots have found comfort in having two of the above. Other pilots have found some comfort is being capable of flying all of these on a partial basis. Being prepared, trained, and capable of flying under partial instruments, for awhile is part of flying competence. Most difficulties occur when partial instrument flying occurs over a long time.

Descent (Decision) Height (DH)
This is the height at which a decision must be made during a precision approach to either continue descent or to execute a missed approach. Since a descent below the DH is not allowed unless the choice between the two decisions is made, the choice must be made before reaching DH. This means that the required visual references must be acquired before reaching DH. Every pilot should have personal minimums as to the DH and should consider executing the missed well before reaching the DH.

The ability of a Part 91 operation to do almost anything that is not in the IFR rules allows the pilot to descend to DH and then take a look. Part 91 operations do not require the pilot have reported weather at the destination. He can take a look. POH performance charts are predicated on a TCH of 50' over the threshold. A displaced ILS or VASI that result in a Threshold Crossing Height (TCH) greater than 50' is going to affect your landing distance.

The decision height (DH) is the lowest altitude to which we can descend on a glide slope.  At this altitude you much either execute a missed approach or land, depending on the visual landing environment. Decision height is a point on the glide slope where a pilot decides between two choices: (1) To continue the approach or (2) To proceed with the missed approach. Once past the DH the pilot still need not be committed to continue. The decision you make at the DH is the most important decision other than those during an emergency.

Knowing what to expect at DH will make what happens move slower only if you have guessed right. Stay on the glide slope when looking for the breakout. Diving for the runway is normal but wrong. You will not hit short if you stay with the slope. The ILS has no visual descent point. On a non-precision approach don't start your landing maneuvers until you have the airport in sight.

Airport in Sight
There are many illusions associated with the transition from IFR approach to the VFR landing. You don’t rely on ground contact. Other illusions of distance, position, are both possible and likely when looking for the airport and runway. Reaching minimums and then finding the airport is not a recommended single pilot operation.

As a single pilot you want to reach visual conditions before reaching MDA or DH. The sooner the better so as to give you a better opportunity to locate the required runway indicators. Regardless, you remain on the ILS, localizer, or heading that will take you to the runway. If circling is required you must not lose sight of the airport nor enter the clouds. Aircraft control is the essential ingredient.

The winning hand on any IFR approach is to have the airport in sight. If visual conditions are marginal you must have horizontal visibility, especially for circling to land. The pre-determined missed approach option is always there as a choice.

IFR to VFR Transitions
Where no radar vectors exist adherence to the published procedure is a must.
--Having runway lights spaces irregularly can confuse pilot perceptions of runway length and height.
--Weather conditions are so dynamic that an approach may be possible for an aircraft in one brief time frame and impossible the next.
--The most critical transition segments of the final approach is from 500 feet through the flare and touchdown. All aircraft should be established on a stable approach during this segment and even more so if visibility is poor.
--Only the ILS provides you a approach with an optimal landing position.
--In the design of the ILS, Category A planes must have one-mile visibility up to 880’. Above that 1 1/4 mile is required.
--On an ILS approach, once you have descended below circling minimums as given for the localizer approach there is no going back up.
--ILS FAF in case you lose the glide slope. Punch your clock.
--Failure to note the time at the Localizer FAF requires you to execute a missed approach any time you lose the ILS glide slope inside the FAF.
--This does not apply if you can identify the missed approach point by other means.
--Move the throttle so that the changes can be heard.
--Set the power to give the speed required during the descent. It is power management that holds the glide slope.
--A 3-4 degree heading change will change needle by one dot.
--Tendency is to fly the needle instead of the heading indicator as you get below 800 feet.
--It is better to accept needle two dots off than to make violent maneuvers.
--The wind does not always decrease at lower altitudes.

Initial Approach Fix
The FAA has determined (1994) that the IAF is a required route in a non-radar environment unless you have a contrary clearance. The IAF can be part of the en route flight where the en route 'feeds' traffic into the IAF. Sometimes these 'feeder routes' are not part of the en route structure. The instrument approach begins at the IAF. The IAF may be along an arc, radial, course, heading, vector, or any combination of these. The IAP chart assures terrain and obstruction clearance and contact with the airport.

Uncontrolled Airport Arrival
It is possible to operate IFR into and out of just about any airport and you can get into some fields even if they don't have approaches. You are filing an IFR flight plan into an uncontrolled airport. There is no instrument approach. The airport has 50 mile visibility and ceiling unlimited. An alternate airport is required! The use of or dependence on a phone both to file and close can create problems since the "single-threading" (one aircraft at a time) of traffic may effectively exclude other IFR traffic due to phone communications failure.

If you should file an alternate and decide to fly there instead of your primary destination, you must re-file another alternate. The pop-up and tower en route flight plan may not be considered by ATC as a legal flight plan since no alternate is given. The correct way to file an IFR plan is through Duats or an FSS. An air file should be done by relay to the FSS.

If in the course of a flight you find that updating weather indicates that your alternate is not legal, find and file for one that meets requirements. The new selection should appear in the remarks section of the flight plan. Every IFR flight is required to have an alternate for IFR operations if the destination is expected to be less than 2000’ ceiling and 3 mile visibility for one hour each side of your ETA. The alternate must have either a precision approach with at least 600 and 2 or a non-precision with 800 and 2.

AWOS/ASOS as now being installed at uncontrolled airports gives a pilot a head start on predicting the need for an alternate. Get the AWOS/ASOS as far away as possible and get an indication of any trend. The trend can motivate an early departure for an alternate. When planning a flight in near-minimum conditions remember the requirements, select obtainable alternates and keep alternate alternates open. Failure to depart for an alternate in a timely manner is an indication of poor planning and judgment.

The IFR clearance to an uncontrolled airport is not a clearance to land. ATC would (normally) like you to cancel IFR well before you get to the airport if conditions permit. Otherwise, you must cancel by phone after landing. They have a way of suggesting for you to close in flight. They remind you be sure to close after landing. If there is the possibility of a missed approach do not cancel your approach into an uncontrolled airport. In the event of an accident you will be out of the system and ATC has no way of knowing that you are overdue. There are enough cracks in the system without you falling through one of your own making. You may still have advisories but any warning of minimum safe altitude (MSAW) and low altitude alert (LAAS) will not be there.

It would be best to monitor the advisory frequency during the approach for other traffic on your #2 radio. When told to contact CTAF be sure to advise traffic that you are on the IFR approach. If circling, maneuver shortest path to base or downwind that conforms with the local direction of traffic so as to avoid conflict with a local requirement. Try to over fly to determine runway and pattern. See and be seen applies. Use the radio. Just because you are IFR does not mean that you have priority over VFR traffic at an uncontrolled airport. Your IFR straight-in approach does not give the traffic "see and be seen" advantages of the preferred 45 entry.

VFR-On-Top
You file an IFR flight plan with VFR-on-top. At 180 degrees magnetic course  you should fly at even plus 500' altitudes. A pilot must comply with VFR visibility, distance from cloud criteria and minimum IFR altitudes from FAR Part 91. ATC services for separation in Class B, Class C and TRSAs. FAR 91.159, AIM Para 266, and FAA Order 7110.65. 

You can file (through the remarks section) for a climb to VFR conditions with stated intention of canceling IFR on reaching VFR conditions. This clearance must be asked for by the pilot. ATC will advise of any top reports if available. If you reach a clearance limit before reaching VFR you can expect to hold. Don't ask for a climb to VFR unless you are certain you will reach VFR at the altitude you've selected.

When traffic prevents a climb or descent on an IFR flight plan being made in visual conditions, you can request a VFR-on-top. When the VFR-on-top is approved by ATC you must obey both IFR and VFR FARs. Your altitude must be correct for VFR hemispheric rule and above IFR minimums. VFR cloud clearances and visibility are required and you are liable for your own traffic avoidance. IFR position reporting and following ATC clearances is required. Altitude changes must be reported to ATC. When being vectored by center in an area where there is no MEA you should query ATC to confirm that the MVA (minimum vectoring altitude is also the minimum IFR altitude.

Continue To Next Page