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Contents

Items that need a home:
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Some fixes are DME only and cannot be called by radar.
--Most non-precision approaches have only 250' of obstacle clearance on final approach. 
--A VOR or NDB with a FAF has 300' 
--Without a FAF  the NDB has 350'
--Sometimes irrelevant, nit-picky fine points have an intrinsic beauty all their own.

Safety Pilots and Medicals
A person is not required to hold a medical certificate...when exercising the privileges of a flight instructor certificate if the person is not acting as pilot in command or serving as a required pilot flight crew member. FAR 61.3(a)
No person may not operate a civil aircraft in simulated instrument flight unless...the other control seat is occupied by a safety pilot who possesses at least a private pilot certificate with category and class ratings appropriate for the aircraft being flown.
The regulation say a safety pilot needs only to have private certificate with category and class ratings appropriate to the aircraft. The regulations are silent that the safety pilot be current and qualified in the aircraft. The instant the pilot puts on a hood the safety pilot must have a current valid medical.
Partial Panel
There should be no change in your control touch between normal IFR and partial panel. A light two finger touch with smooth pressures works just as well with partial panel. The partial panel scan, in many respects, is easier because to some degree the number of instruments to be scanned is reduced.  So long as you avoid any extreme attitudes or abrupt control movements partial panel is not very difficult to fly. Once the equilibrium of the aircraft is disrupted partial panel flight requires very considered control input and power applications.
Partial panel requires that the pilot have at least one pitch and one bank instrument always in the scan while using the compass and altimeter and turn coordinator to verify performance. Heading changes are best made incrementally using the count method. One, two, three, level, verify and repeat as necessary. I suggest doing it three times this way to make a 20-degree turn. Insist that ATC give any vectors to require a minimum of maneuvers to get established for an approach.  Try for an ILS or possibly a GCA or radar assisted approach if possible. Your turn coordinator is used to maintain heading.
You must know your aircraft performance numbers and required configuration to maintain a pre-determined approach speed. Any speed above Vref for your aircraft weight puts you in danger of self-destructing. Under partial panel you may well be better off to slow to approach speed immediately to avoid exceeding Va. Should you get into a high-speed situation you should first level the wings using the TC and reduce power before initiating recovery. A bank will add stress to the structure. Avoid any turns (bank) when in an uncontrolled descent.
A low-speed situation compounded with loss of control requires that the angle of attack be reduced, the wings leveled, and power advanced at least to low-cruise. Get everything stabilized before attempting to get any assigned heading, altitude, or speed. It would be well to practice partial panel stabilization procedures to set firmly in place just how you stabilize yourself from the slow and fast conditions.

Oddly, some pilots find partial panel easier than full panel. This happens when the pilot flies in such a way that the airplane is not part of the problem. In partial panel caused by vacuum failure the altimeter, VSI, IAS and power sets attitude. Heading uses the compass and timed turns to change headings. Wings level uses the turn coordinator.
Partial Panel Items
--Declare an emergency and advise ATC that you are flying, "No gyro". ATC knows not 'partial panel'.
--One peek is worth a thousand scans.
--Vertical card compass is great asset to partial panel flying.
--Needle, ball and airspeed skills are essential skills, in my case, that was a first learned way of flying IFR.
--There is no way to realistically simulate the sensational conflicts of actual conditions spatial disorientation.
--A vacuum failure light is initially more important than partial panel skills. It tells you when PP is needed.
--Gradual loss of electrical or vacuum power that results in gyro failure cannot be simulated in your aircraft.
--The compass and AI are least likely to fail. Believe them with conflicts of data occur.
--Delay in recognition of need to go on partial panel will get aircraft beyond point of recovery.
--The gradual failure of gyros leads the pilot to follow just long enough to be beyond point of recovery.
--It is the conflict between what you see on instruments and what you feel that causes disorientation.
--Without the AI and HI you have a stage set for spatial disorientation.
--Instinctive pulling back on the yoke only tightens the turn, increases G-forces and descent rate.
--Critical attitudes must be detected and stopped immediately.
--Duration of partial panel is inversely relative to likelihood of maintaining control under stress.  Head for VFR
--Critical attitudes or unusual attitudes require frequent review.
--Once under control, level and trimmed fly only with rudder.
--The less you touch the yoke the more likely the aircraft is to remain under control. Avoid aileron use.
--Rudder flying is done by pressures and anticipation especially in making turns. Standard rate or less.
--Prepare for partial panel flying by practicing rudder only flying as often as practical.
--Descend by reducing power. Level off by anticipating with 'level' power. Climbs need power and rudder.
--In retractables use landing gear to descend and regain level flight.

Things to Know About Partial Panel 
--Distractions galore for the unprepared
--Spatial disorientation will occur
--Slightly over 10% of total annual accidents
--Less than 10% are vacuum related
--Complex high performance most likely to cause disorientation
--Training needed for all possible failures that's impossible in planes.
--Speed up your scan and keep a light touch on yoke.
--Recognition of the failure is the first essential.
--Gyro instruments take several minutes to completely fail. Always check the turn coordinator.
--You should cover the failed instrument with post-it, paper money or what ever. Use gum as glue.

Holding Headings
Partial panel tracking of a bearing or radial can be done using the turn coordinator, which is primary for holding headings under partial panel. Any flight from wings level shows immediately on the turn coordinator or needle. By flying the needle/TC as primary for heading very accurate headings and bearing/radials can be flown. Many pilots find that bracketing using the needle/TC is actually easier than using the AI. Therein can lie a problem.

Aside: I once had a pilot come to me after 130 hours of IFR instruction and a checkride failure. On our first flight into actual conditions, we had a turn coordinator failure just as we entered the fog. The failure was noted immediately by the student. He had only used the turn coordinator for holding wings level. However I was unaware of this until he attempted an ILS approach and was completely unable to either fly the plane or fly a heading. I had to take over and cancel the approach while climbing to VFR. The subsequent flights were flown without the turn coordinator until he used the AI as primary for wings level.
A heading does not change if the needle is centered. A heading does not change with wings level turn coordinator.  Heading control is perhaps the most essential element of attitude flying. The turn needle and the turn coordinator are primary for heading control under partial panel. These do not reveal bank angle except in so far as the pilot is able to relate the standard rate turn and airspeed into an angle. A needle width turn is the same as a two-minute turn coordinator turn.
Before flown in actual conditions both the needle and the turn coordinator should be calibrated by making level standard rate indicated turns and clocking it with the number of degrees turned per second. Standard rate turns and holding headings under partial panel is totally dependent on the ability of the pilot to fly using an absolute minimum of control pressures. This means no more than one finger and thumb used to move the aircraft off of its trimmed attitude. It is relatively late to learn to fly this way if you have not flown that way since you started flying. A tight grip will result in over control and loss of controlled flight.
The type of partial panel emergency you can expect is directly related to the way your aircraft is equipped. The traditional vacuum failure is only one of several ways it can happen. The best solution to any emergency is to get to the ground flying VFR. A partial panel emergency that extends for any period is likely to result in an accident.
The record of IFR accidents shows that many pilots were unable to control the aircraft on partial panel. A partial panel accident is most likely to occur when the pilot has not opted to go to the nearest VFR conditions.

The only way to fly without the AI is to be able to fly needle (attitude indicator), ball, and airspeed. The other gauges such as the altimeter, DI, (compass), VSI are all telling you in their own small way what is happening. The only thing that will save you without the AI is the speed with which you scan the remaining instruments.
Without the attitude indicator a pilot will tend to over control and not make the required small corrections. Once you have noticed that you are reacting instinctively to the remaining instruments you can avoid the problem by taking out at least half of any initial reaction. At a major military airport such as Travis, you can obtain a surveillance approach in which you fly the heading corrections given without any radio reply. Flying a specific heading with a GPS set to your VFR destination is relatively easy. Try it.
The worst time to study emergency procedures is when you have one in progress. You can only prepare for the partial panel emergency by practicing the procedure and studying how the condition can be recognized quickly. The first response must be to cover any inoperative instrument. Use no-peekies or even large post-its. Should your aircraft have a vacuum back-up, should at least be familiar with how to get it operating along with possible limitations.
In actual IFR conditions a failure can best be handled by knowing where the closest VFR conditions exist. The extent to which you are familiar with your aircraft is perhaps the most important element of partial panel survival. You must know the power settings, airspeeds, sounds and all their variations to enhance your chance of survival.
The lack of partial panel practice will deteriorate your scan skills. Partial panel proficiency is the most perishable of instrument skills. Your skills usually coincide with your equipment and the frequency of use. You tend to use well what is there to use. Being reduced to basic instruments requires the use of skills seldom practiced. Accidents happen when the abnormal occurs. The basics of partial panel are heading, altitude, and airspeed. Don't expect ATC to fully understand your partial panel problem unless you give a full explanation.
Knowing what power settings provide the control equilibrium for any desired flight condition makes partial panel approach feasible. You want to get lined up on final as far out as possible. As an approach indicator the compass is just too erratic especially inside the FAF. Once you know the course fly with wings level and the ball centered. Don't chase the needles, use rudder for instant, quick and small corrections. Since you are flying headings, keep the wings level.
It would be a rare instance for pitot-static, vacuum and electric system to fail together. The best defense of a failure of one is to have an operational/available backup system. The better your cross-check the sooner you will notice a problem. AI cross-check is Altimeter, VSI and airspeed. Heading cross-check is the TC and compass. airspeed check is altimeter, AI VSI and power. Altitude check is with VSI, AI and airspeed. Practice partial panel often.
Partial panel practice exercises. Hold altitude and airspeed as constants. With power as a variable, control airspeed with power and altitude with pitch. Practice 180 and 360 compass turns both left and right. Vary airspeed while maintaining level flight. Make timed turns to headings. Practice rate-climbs and descents. Practice stalls and unusual attitude recoveries. Allowable error margins of 100', 10 knots and 10 degrees.
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