The Fix
The hold is a race track pattern which, in no-wind conditions, is made up of one minute straight legs and one minute turns at each end. At one 'corner' of the pattern is a FIX. A FIX may be the airway intersection of two VOR radials, a VOR, an NDB, by DME along an airway radial or by direction. The pattern is normally flown at an economic fuel saving speed. If you are being flown toward a holding pattern by ATC, make a request for a lower (endurance) speed en route. This lower speed may eliminate the holding requirement. Always plan to slow down before reaching the fix. Sooner is better than too late. The turns are not normally timed since a standard rate turn is used and may be more or less than 180 degrees for windage.

There are rules about what angles radials are used to intercept at intersections. When procedures are designed, the protected airspace takes into account things like fix uncertainty due to poor navaid geometry. Once established in the holding pattern at an intersection fix the needles will be centered at the fix, both needles will be off on the outbound leg and one centered on the inbound leg. At a VOR the fix is reached at the moment of TO/FROM reversal. The needle is off to one side on the outbound leg. NDB holding will be covered later. The first big step to holding is aircraft control. You must have your power/trim settings for the aircraft so locked in that neither airspeed nor altitude become distractions or added work load.

Historically, the name of every intersection made some reference to something near that location. Originally the words were spelled out. With the advent of computers all intersections consist of five letters which may phonetically resemble the original. LODI became LODDI, RIO VISTA became REJOY and VISTA. Only an active imagination or an old memory bank makes possible many of the associations. VORs have only three letter designators.

Early attitude indicator gyros were quite subject to precession if a continuous turn were made. To prevent this as a problem holding patterns were designed with one-minute straight legs. Hence, the holding pattern as we know it.

In the real world of holding where it is an every flight occurrence at certain Class B airspaces, the pilot knows just by 'situational awareness' what he must do to position the aircraft to the fix and into the holding entry. You just know what to do and how to do it. There is no need for diagrams, angles, or mental gymnastics.

The General Aviation pilot will do more holds getting the IFR rating that he will ever do the rest of his flying life. It is because of this lack of use that the pilot must have an easy, available method for interpreting the clearance and determining the holding procedure.

Information provided by ATC:
--The direction from the fix is given (confusion issue) including the radial or bearing to hold. This holding direction is the side to hold on but is not the course for the inbound direction.
--Know when you arrive at the fix and make your outbound turn within six seconds.
--One minute holds are made up to and including 14,000’. Know that the true airspeed over indicated airspeed increases with altitude.
--Using a DME hold requires that you change your time for a leg into a distance for a leg. Thus, at 90 knots a leg would be 1.5 miles for one minute. Using DME you would turn after 1.5 outbound regardless of time.
--Expect further clearance (EFC) is required information for a hold. If ATC fails to give it, ask for it.
--You are expected to used all available resources.

Timing
You start timing the outbound leg of intersection, VOR, and DME holds when you are on the selected outbound heading as corrected for wind. The traditional practice has been to double the outbound wind correction angle on the outbound heading. As of January 6, 1995, the AIM uses the word triple' instead of double. At an NDB or if you can establish when abeam a VOR or a fix start your time when abeam. VOR: Outbound timing starts when to/from indicator reverses as you pass abeam the VOR.
Intersection: Outbound timing starts at completion of outbound turn since magnetic bearing cannot be determined.
NDB: Outbound timing starts when ADF relative bearing is 90-degrees minus drift correction angle.

Timing Using the E6-B Flight Computer
Correct description is:
Set the actual outbound time, on the outer ring, opposite the actual inbound time, on the inner ring. Now read off the correct outbound time from the outer ring opposite the 60 second arrow on the inner ring. So, for example, if your first outbound leg is 60 seconds, and your inbound leg after that is 45 seconds (because you have a tailwind inbound), you'd set 60 seconds on the outer ring opposite :45 on the inner ring, then read off 1:20 on the outer ring opposite the 60 second arrow on the inner.

So, let's say you fly the next outbound leg for 1:20, and on the inbound you still only take :50. Shift the ring so that :50 is opposite the 1:20 (that used to be next to the 60 second arrow); you should now see 1:36 opposite the 60 second arrow, so that's what you should fly the next outbound leg. All it is doing is 60 * (outbound / inbound).

Holding Airspace
The space available for the hold is fairly standardized both as to length and size to each side of the inbound course. There is a primary area, maneuvering zone, and secondary area. The overall shape is like that of an elongated avocado cut in half lengthwise. The fix is on the course line. One nm away, at right angles to the course at the fix, is the center (nameless) of the radii for the small end of the avocado. A five nm 180 degree area of arc forms the small end of the avocado. Ten nm away on the outbound course there is another point (nameless) on the same side of the course but two nm miles from the course. The six nm radii from this point form the big end of the avocado. The offset from the course line of these two points gives both ends of the maneuvering zone. The course line is thus offset from the center line of the avocado by one nm on the small end and two nm on the big end.

Draw an avocado. The holding inbound course line is offset to the non-holding side one mile from the center of the arc of small end and is offset two miles to the non-holding side of the arc of the large end. The radius of the small end arc is 5 miles plus a two-mile secondary zone which extends like a heavy skin around the avocado. At its longest the avocado is 25 miles long. At the large end it is 15 miles wide and at the fix about 14 miles wide. The holding side gives us a over half an avocado that is 25 miles long, and widens from 7 miles to 10 miles on the holding side. The non-holding side is 23 miles long and 7 miles wide.

Holding patterns are used instead of procedure turns to reduce the amount of airspace required. The procedure turn can be any time you want as long as it is to the correct (protected) side. Caveat: Some Category A-only require reversal within 5 miles. It does not need to be as depicted unless it is a teardrop. Personally, I much prefer the 90° /270° since it is quicker and reduces potential wind effect.

There are specific rules about what angles radials are allowed to intercept at intersections. In theory, you could define an intersection of the 180 radial off one VOR and the 190 radial off another, but in practice the two cross at so shallow an angle it would be impossible, as you discovered, to locate the point accurately enough using VOR receivers. When procedures are designed, the protected airspace takes into account things like fix uncertainty due to poor navaid geometry. So, even though it looked like you were having troubles finding the fix, you were probably still within the protected airspace, which is all that's required.

ATC Directions
They are; NORTH (exactly 360 but ranging between 340 and 020);
NORTHEAST (exactly 045 but ranging between 020 and 070);
EAST (exactly 090 but ranging between 070 and 110);
SOUTHEAST (EXACTLY 135 but ranging between 115 and 160);
SOUTH (exactly 180 but ranging between 160 and 200);
SOUTHWEST (exactly 225 but ranging 200 to 250);
WEST (exactly 270 but ranging between 250 to 290);
NORTHWEST (exactly 315 but ranging between 290 and 340)

Sum-of-the-Digits. (Use numbers immediately above)
Notice, bold digits when added equal 9.
Notice, italicized digits when added equal 7
Notice, normal digits when added equal 2 (2+9+0 = 11; 1 + 1= 2 )

The Pilot Must Know:
--How to fly from cruise to 90 knots and back again at altitude
--Right from left
--That a radial is from a VOR, a bearing is TO an NDB
--The numbers and terms for major headings of the compass
--How to get reciprocals quickly. (+ 2 and + 2).
--Using the DG to get reciprocals, 30 and 45 degree angles
--How to fly with minimum effort TO/FROM a VOR radial.
--How to intercept and track a given bearing to an NDB
--How to quickly tune and set radios is important.

Radar/Radio Surveillance
--ATC communications are guaranteed at MEA and expected at IAF and at Missed Approach altitude but not necessarily on approach.
--Where possible ATC is required to detect and advise any time the holding airspace is exceeded. However, it is the pilot responsibility to maintain the hold, not ATC's.
--If, when under radar, you should ever acknowledge that you have visual contact with pointed-out traffic it becomes your responsibility to both see and avoid. ATC has effectively handed this responsibility to you until you should again tell ATC that you can no longer see the traffic. Better to not see??
--Yes the ATC system does fail but more common are mistaken frequency assignment or a dropped handoff. You can protect yourself by anticipating your next frequency. This can be done in your preflight planning, referring to your charts, using the A/FD listings, or most easily listening to the handoffs that occur in front of your flight. The last method is best because it is the least likely to be out-of-date. During busy and non-busy periods ATC will eliminate or combine station frequencies. When you know which period exists during your flight you can anticipate the required frequency.

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