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In the Beginning
For many years the search was on for a zero-zero system. This has only in the recent past become possible. Once a 200-foot minimum was accepted as the best available things began to improve.

In 1918 the first marker beacon was demonstrated. In the early twenties the first four-course radio range was demonstrated. This could get you from point to point but not on the ground.

In 1928 the concept of an ILS with the heavy equipment on the ground and the indicators in the airplane was accepted. A cooperative effort by the Guggenheim Foundation used Jimmy Doolittle to contact the Sperry Gyroscope Company to get them to develop two needed instruments. Sperry created an artificial horizon (Now called an attitude indicator) and a gyrocompass (Now called a heading indicator) which gives precise and easily determined information. Doolittle used a localizer beam to guide him to the airport and a fan-marker as a means for determining distance from touchdown. The last remaining necessary instrument came from the Kollsman Instrument Company. In August of 1929 Kollsman perfected a barometric adjustable altimeter that gave vertical information within 20 feet. At the end of September Doolittle flew a localizer approach to touchdown

At the same time a high frequency glide slope beam was being developed at College Park, Maryland which by 1931 was blended into a three element landing system consisting of a localizer, marker beacons and glide slope. Marshal S. Boggs made a blind landing on a runway whereas Doolittle had landed on a large field. Boggs' localizer was accurate to 20' at the threshold. The glide slope was accurate to five feet when 30' above the ground. Boggs made over 100 such landings but always with a safety pilot. Jim Kinney took over for Boggs who was killed while on vacation. Kinney completed the first IFR flight from takeoff to landing by flying in clouds from College Park to Newark. Lindbergh made two ILS approaches using a safety pilot. The project was killed in 1933 by the withdrawal of federal funds due to the depression.

When the federal government dropped the ball the airlines were interested but an ILS system cost over sixteen thousand dollars and $600 more to equip an airplane. Then when the expensive airmail contracts were canceled, the U.S. Army began flying the mail. In five months there were 66 accidents. Then the government became interested in a landing system, not the ILS, but an NDB system with markers. Using this system Lt. Al Hegenberger made the first solo blind landing ever at McCook Field Ohio. Because of Hegenberger this system became the government's favored system and it was so primitive that it could be federally financed because it was not an airport improvement. The airlines were unhappy, knowing that the ILS was waiting in the wings.

TWA developed and tested a high frequency ILS system in Germany but again it was not precise enough for the airlines. In 1935 some scientists who had left the previous government ILS started their own company and developed a portable ILS that could be moved from runway to runway. This system was supported by and adopted by the Navy for land use.

In 1934, United Airlines acquired the original Newark ILS equipment and moved it to Oakland, CA. This was installed as a permanent ILS as modified in 1936. In March of 1936 R.T. Freng in a Boeing 247 flew an autopilot coupled ILS approach. Over 3000 such approaches were flown over the next two years. Other airlines, and the military services were involved.

When five airline crashes occurred in December the government initiated a well financed airport modernization program. In 1938 the first passenger-carrying airline landed at Pittsburg, PA using the ILS in actual conditions. The first United-Bendix ILS systems were installed at Burbank, Oakland, Kansas city, Chicago, Cleveland and Newark. In June of 1938 the 1926 was erased from the books. However, before All airline pilot training, commercial pilot training, air force pilot training, fighter pilot training, pilot training schools, flight training schools, flight attendant training, helicopter flight training, accelerated flight training, airline flight training, flight training florida, flight attendant training schools, instrument flight training, cpl flight flying school training training, flight training simulator, flight training academy, atp flight training, helicopter flight training schools, california flight training, professional flight training, data flight training, orlando flight training, corporate flight attendant training, flight nurse training, warrant officer flight training, flight training device, lufthansa flight training, flight training san diego, alien alien flight flight training, military pilot training, sport pilot training and private pilot training.

ILS Charts in the Making
Charts are made following the rules of FAR 97 which requires that a text presentation of the chart be made as a proposal or a proposed rule making based upon the U.S. Standard for Terminal Instrument Procedures or TERPS. +Safe flight is the primary basis of chart design.

1. Obstacle clearance slope is folded in with the need for a smooth descent.

2. TERPs standards are followed as much as possible.

3. Non-TERPs standards must be fully documented.

4. User and other agencies have time to make comments.

1. Initial approach made of DME arc, radial, course, heading vector or a combination as the initial approach fix (IAF) as a beginning point. This segment has 1000 feet of altitude above an obstacle and narrows from 4 nm to each side of center at 13.5 miles from the threshold down to1/2 m at the inner marker. A secondary area gives 500' obstacle clearance beginning at the 4-mile primary area to 6 nm and narrows to the same 1/2 mile at the inner marker as the primary area.

2. Intermediate approach begins at the end of the initial approach segments where you configure the aircraft and adjust the speed while setting up on the positive approach course.

3. Final approach begins at the FAF and ends at the runway of missed approach point.

4. (Optional) The circling approach has a region adjusted to the speed of the aircraft. The maneuvering area allows the aircraft to remain with the airport in view while it flies to arrive in alignment with the runway before initiation of the descent.

5. The missed approach is a point from which the aircraft rejects landing as a possibility and climbs to depart the procedure.

IFR Approach Basics
Flying the ILS requires the pilot to process four times the information a surgeon doing a major operation. Outcome is result of three basic factors:
1. Pilot’s knowledge of aircraft
2. Pilots ability to fly smoothly and competently
This is region of greatest weakness. Pilot must have ‘feel’ for what the airplane is doing. You must learn to slow the aircraft to approach speed at a time and place commensurate with your altitude and the required airspeed configuration.
3. Situational awareness.
You must know exactly where you are in relation to the airport and final approach fix. When you are in strange territory and have unfamiliar approaches and departures, the wisest thing to do is to ask for help from the locals. You can expect that every departure will be somewhat different due to local procedures that often bypass those published. Expect to get an amended departure in the run-up area that differs from everything you have planned. Expect that with the advent of GPS that even your enroute plans will be augmented by GPS-direct to an intersection that bypasses a busy corridor.

The criteria of IFR proficiency is based upon your ability to adapt to the unexpected. An instrument departure is given in your clearance as a road map. Before flying any part of the departure, enroute, arrival, or approach you MUST review not only what you expect but what you may get. Major problems can result if any part is totally different from what you planned. As to what causes these differences it may be due to weather, aircraft performance, human limitations, or even ATC restrictions. Getting or requesting radar vectors is often a valid option.

In the planning of IFR flight you must pick off as much in the way of names, courses, distances, frequencies, and change-over points, and minimum altitudes from the plates and charts as seem to follow your route. Expect ATC to be as helpful as they can be in giving you requested altitudes, deviations, or special considerations. Let them know if you have a problem and keep them advised of any significant changes. You want to know your chart information so well that any search only takes the recommended three seconds off your flying scan.

In the flying of IFR scan is your first priority. If a clearance disturbs your scan tell ATC to give you a heading long enough for you to get the rest of the clearance. Single pilot IFR is ten times more difficult than two pilot IFR. Even with autopilot, single pilot IFR requires more practice and proficiency that is required when two pilots divide the work load.

The student who chases the localizer and glideslope needles by jockeying the power and elevator is going to be in ILS trouble when the funnel narrows.
--Cover up the AI.
--Have student concentrate on the DG, VSI, and airspeed.
--Set power to get the desired approach speed and descent rate.
--Crosswind components usually decrease with altitude.

Prevention Plan for ILS Mistakes
Just as an accident is preceded by a series of judgment mistakes, so is a defective ILS approach preceded by a series of planning errors. Well away from the airport get the ATIS; Check the FSS for recent NOTAMS. Review the plates. Confirm the basics of the Missed. Listen to what is happening to aircraft ahead of you. Check to make sure that you get what you expect in descent and headings. Set up your GPS as a situational awareness guide. Expect to execute the missed. Review your pitch and power setting for every stage of the approach. Remember: Wind will never be what they say it is.


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