THE TO FLY AT NIGHT . . .

SPORTPLANE BUILDER By Antoni (Tony) Bingelis EAA Designee Program Advisor 8509 Greenflint Lane Austin, Texas 78759

A

MAJORITY OF the two-seater homebuilts at Oshkosh this year appeared to be equipped with an assortment of position (navigation) lights and landing lights. But, anti-collision lights, which are mandatory for night

FAR Part 91.33 states that each light must be an approved type. However, I've seen homemade installations where a common automotive bulb (without any cover)

flying, were noticeably absent on many of them. Does that mean none of these airplanes are used for night flying? I wonder??? I wonder also how many of the builders of these same aircraft were jolted at some recent recertification period when they first learned from their FAA inspectors that they could not operate their homebuilts at night because they were not properly equipped. You know, it seems like only a few years ago all that was really needed on an airplane for night operations was a red navigation light out on the left wing tip, a green one on the right wing, and a white tail light. Alas, this

was screwed into a socket affixed to the aircraft where it served as a white tail light. A similar arrangement was effected for the wing tip lights except that over each of them was a red or green plastic cover. Be careful though, an installation like that might strike your local FAA inspector as being unsuitable . . . even under the flexible Amateur-Built classification. Each of the three position lights are installed so they will project an unobstructed light pattern of 180" plus or minus 90" vertically. Laterally, the wing tip lights should be visible through a range of 110" left and right from straight forward. The white tail light should cover a range from straight back to plus or minus 70" either

is no longer true. Now, should you want to fly at night, your homebuilt must be equipped to comply with the current FAR Part 91.33c, Visual Flight Rules (Night), other-

side of the tail. Refer to Figure 1 for an instant clarification.

wise the FAA EMDO inspector will not . . . cannot amend the aircraft's Operating Limitations to include that privilege. NIGHT VFR REQUIREMENTS

What are the requirements for flying night VFR? In addition to the instruments and equipment specified for VFR flight (FAR Part 91.33c) you must have installed on your aircraft: 1. Approved Position Lights (Many of the current crop of homebuilts already have these installed.) 2. An Approved Anti-Collision Light System. 3. Spare fuses (unless you have circuit breakers). 4. Finally, and this is a requirement, believe it or not . . . an adequate source of electrical energy. As you know, homebuilts cannot be operated for hire therefore, the mandatory requirement for one electric

landing light can be ignored. For all practical purposes that's all. POSITION LIGHT INSTALLATION

These are the lights most of us think of when we think of installing lights. The entire night flying system is designed around position lights and all other lights must be installed so as not to detract from their conspicuity. The forward position lights must consist of a red and a green light spaced laterally as far apart as practicable. These are installed forward on the airplane so that with the airplane in normal flying attitude, the red light is on your left wing tip and the green light is on the right tip. A rear position white light must be mounted as far aft as practicable. All three lights must be hooked up to form a single circuit so that all will light up simultaneously when the light switch is turned on. 12 DECEMBER 1977

Those of you with existing position light installations should check to see if you are getting sufficient light pattern coverage. The standard E series wingtip navigation light (Figure 1A) is highly recommended for any installation as it is small, neat and easy to install. The white tail light often requires some modification of the trailing edge before it can be accommodated. This is one good reason to decide during the construction phase whether or not lights will be installed. The navigation lights each have only one wire which runs to the cockpit NAV light switch, circuit breaker

(or fuse) and bus bar. The base of the light serves as the ground connection when installed in all-metal aircraft. Installing these lights in wood wings, fiber-glass wing tips or composite structures requires the addition of a ground wire. You can do this by soldering a wire to the base of the light and running its other end to the closest grounding point. ANTI-COLLISION LIGHT SYSTEM INSTALLATION

The requirement for an approved anti-collision light system became mandatory for all powered civil aircraft with Standard Category U.S. Airworthiness Certificates

on August 11, 1972. "Aha," you say, "Mine is a homebuilt and not a Standard Category airplane, therefore . . . " Good thinking amigo, but be advised that the rule has been interpreted as also being applicable to homebuilts. As a matter of fact ALL airplanes flying at night must now have anticollision lights installed. Navigation lights alone are insufficient. Homebuilts with Operating Limitations issued prior to August 11, 1971, can get by with only a token compliance as only 100 ECP (effective candle power) is required to fulfill their anti-collision lighting

requirements. On the other hand, any homebuilt whose

\

Typical position light installation properly located. Strobe lights could be mounted on the fuselage or added to the position lights to update this installation to meet current requirements.

This modified wing tip position light has a shield installed to protect the pilot's eyes against the strobe light flashes.

This light installation is aerodynamically clean but offers marginal results in meeting FAR Part 23 light intensity and pattern requirements.

A homemade strobe light installation nested with a conventional Nav. light in a tin foil backing. Light pattern and intensity are probably poor for the strobe light.

original Operating Limitations was issued after August 11, 1971 must have an anti-collision (strobe) light system that complies with the revised 400 ECP requirement. Most suppliers of aircraft lighting systems (such as Grimes, Whelen, Aeroflash, etc.) put out a piggy-back strobe light modification for the conventional wing tip lights. Installation is simple. All you need to do is drill

a quarter inch diameter hole in the base of each wing light for the strobe wires. Some strobe lights utilize a single power supply unit which can be mounted to any convenient location in the fuselage. The Aeroflash strobe units employ two small strobe power supply units. One such unit is fastened internally to each wing tip rib. The strobe light tube is connected and assembled to the navigation light housing.

A small wire is then run from the strobe switch in the -cockpit to each of the power supply units. Of course,

this type of installation makes it necessary to have access to the wing tip rib. No problem if the tip is a typically removable fiber-glass cover. Otherwise, an access hole

The position light and anti-collision strobe light are recessed in the forward portion of the tip tank. It is unlikely that required light pattern is being obtained for either light system.

in the wing will be necessary.

Units commonly sold by Whelen and Grimes use, for the most part, a single power supply designed to flash two wing tip strobe light head assemblies simultaneously SPORT AVIATION 13

MINIMUM C O V E R A G E RED AND G R E E N WING

TIP

AFTER

SOLDERED

I

,.N

TO PUWER S U P P L f UNIT

'grouna *

if n e e a e d f '.

FIGURE

2.

1. The minimum would be the installation of a single anti-collision strobe light on the vertical fin

[ B. )

ANTI-COLLISION

LIGHT

S Y S T E M (MINIMUM

FIGURE

FIELD

OF

COVERAGE)

I.

of the aircraft. This means may be acceptable for only a few aircraft configurations, however. 2. The most practical means of assuring adequate coverage is to add a piggy-back type of strobe light to each of the two standard (Type E) wing tip position lights. See Figure 2. 3. In most cases when the position lights are enclosed in the wing tips, a third strobe light must be added to obtain the required light pattern. This

or in an unsynchronized manner depending upon the type of power supply unit used. These however, require the use of more wires in the installation. Radio interference could also be a factor with the fuselage mounted power supply. Electrical power requirements of course, will increase with the installation of anti-collision lights. A two strobe light installation, for instance, will draw from 2 amps to 5 amps depending upon the power supply units used. Flashing Characteristics Store bought strobes will flash with a frequency of between 40 and 100 cycles per minute. If you are building your own unit from one of the designs available, be sure that your unit flashes within this flash frequency. But, before you start dreaming of saving yourself a bunch of bucks by using homemade strobe lights, check with your FAA inspector to see whether such equipment is acceptable within his office's guidelines. No use proceeding with an installation which cannot later be approved. Field of Coverage The anti-collision system as installed must consist of enough lights to illuminate the vital areas around the airplane. Specifically, when viewed from a distance as close as 1200', the strobe lights should be visible from any direction and provide a field of coverage extending at least 30° above and 30° below the horizontal plane of the aircraft. See Figure 1-B. It is usually unavoidable that small areas of the aircraft will block out the strobes from some angles. This is generally acceptable. There are different types of installations which will meet the light pattern requirements for an anti-collision strobe light system. 14 DECEMBER 1977

third light may be added to the tail or to the vertical fin. If mounting space is a problem some companies sell a combination tail position and strobe light assembly which can be used to replace the original white light.

4. Another common method of obtaining the required coverage is to mount one strobe light to the belly of the fuselage and one to some location on top of the fuselage. Two strobes would be necessary to achieve the required vertical coverage in such an installation. Great care must be taken when selecting the mounting position for the fuselage top strobe. It must be located on the centerline so that as to reduce reflection (on low winged aircraft). Furthermore, its direct light

must not impair the pilot's vision or otherwise create a disturbing environment in the cockpit. For that matter this caution is also applicable to all other lights. LANDING LIGHTS

As previously stated, it is not necessary to install a landing light on a homebuilt as it will not be flown for hire. However, is there a night flying homebuilder amongst us who would install a lighting system for his

homebuilt and not include a landing light? Maybe, but not likely.

Be sure that it provides enough light to be useful in

making night landings. (A sealed beam should put out

at least 100 watts to be considered useful.) Also, if landing lights are installed they must not create a dangerous

glare for the pilot or reflect annoying flashes off the propeller.

Store bought aircraft emit a landing light beam spread

of approximately 13° horizontally and about 11° vertically. Obviously, if this light is to be used primarily for taxiing a wider horizontal spread is desired to improve

peripheral vision. Always place the landing light on a

separate circuit adequately fused to take the rather high ampere flow. Another consideration. Mounting the landing light in the leading edge of a cantilever wing could be risky structurally if the designer has not approved such an installation.

OPERATING LIMITATIONS

In the end, all your preparations and installations not withstanding, there must be authorization in the aircraft's Operating Limitations to fly the homebuilt at

night. This authorization or amendment of the Operat-

ing Limitation is worded something like this in my area of the state of Texas. INSTRUMENT LIGHTS

Don't overlook the need for each instrument and control to be easily readable and discernible at night. Potential problems with cockpit lights, are direct rays and rays reflected from the windshield or other surfaces which

can shine in the pilot's eyes and play havoc with his night

vision. Individually lighted instruments are nice but expensive. Incidentally, don't think for one minute that

a cabin dome light can serve as an economical instrument light. Again, night vision would suffer.

[X]" . . . Day/Night flight VFR only when properly equipped." You will notice from that that the burden of proof that the airplane is properly equipped for night flying

is with the owner and not with the FAA inspector. If you have an installation problem with the aircraft lighting due to peculiarity of design I suggest you refer to FAR Part 23 (23.1381 thru 23.1397) for detailed installation requirements and engineering data.

(Photo by Dick Stouffer)

The EAA Air Museum's XP-51 at the instant of lift-off. In black and white, Charlie Day's superb paint job makes the airplane look like its original bare metal configuration. SPORT AVIATION 15

chapters c n in a tio By Ron Scott Chapter Executive Director

Hi there! Question of the day! With the Advances in amateur built designs, new materials, small "N" numbers, triple snaps and lomcevaks, what are we, the Chapters, doing for the youth

interested in aviation today? Yessir,

these young'uns are the designers and builders of tomorrow and we,

the Chapters, should all strive to expose them to aviation and the EAA

so as to kindle the little fire that in many cases has just barely started. Jim Putney is one gentleman who is doing this very thing. Jim is advisor to the EAA "Skyline" Junior Chapter 440 of Dallas, Texas. It was 16 DECEMBER 1977

a momentous occasion when Isabelle Wiske, our Chapter Executive Secretary, and I opened Jim's letter finding 18 brand new junior membership applications. "Spirit" pilot Gene Chase had the opportunity to chat with the lads at Dallas where the Skyline Chapter helped with crowd control during the Lindbergh Commemorative Tour stop.

I dropped a line to Jim a while ago

asking that he give us some insight on his Junior Chapter 440 and his method of accomplishment. This is

his reply . . .

(Photo by Lee Fray)

Your Chapter Director and Executive Secretary, Ron Scott and Isabelle Wiske, look over the junior membership applications forwarded

to them by Jim Putney, Dallas, Texas.

Dear Ron: I received your letter some time ago and have meant to get right back

with an answer but, as you can see, am a little late. However, I did enjoy getting your letter and intend to help

where I can. Our Junior Chapter here is set up

in the aeronautics cluster of the Career Development Center of the

high school. This is an ideal situation, since we can utilize time during our three hour class period for club

activities. We meet every other Wednesday and have a different group in the morning and afternoon. For the past couple of years, it has