FAA lighting laws, must there be strobe?

Don't know where to post this and didn't find anything when I searched the forums. Please move to appropriate forum if this is not the one.

What are the laws regarding lighting on aircraft in the US?
Can a plane have no strobes, and only one color (white)?
I was under the impression that planes, and most I have seen, are to have at least one strobe and usually a red light somewhere.

I ask because I saw an aircraft come off of Lake Michigan at lower altitude and rather high speed, that appeared to have a symmetrical array of 6 white lights, solid with no strobing and no other colors. The lights where unusually bright, so much that the shape of the aircraft was masked by the light (it was just after dusk.) There appeared to be two rows of lights, 3 per row, in parallel.


Thanks Richard Price for the response, that helps.

[edit on 14-8-2007 by Ionized]

[edit on 14-8-2007 by Ionized]

FAA FAR Part 91.209

Sec. 91.209

Aircraft lights.

No person may:
(a) During the period from sunset to sunrise (or, in Alaska, during the period a prominent unlighted object cannot be seen from a distance of 3 statute miles or the sun is more than 6 degrees below the horizon)--
(1) Operate an aircraft unless it has lighted position lights;
(2) Park or move an aircraft in, or in dangerous proximity to, a night flight operations area of an airport unless the aircraft--
(i) Is clearly illuminated;
(ii) Has lighted position lights; or
(iii) is in an area that is marked by obstruction lights;
(3) Anchor an aircraft unless the aircraft--
(i) Has lighted anchor lights; or
(ii) Is in an area where anchor lights are not required on vessels; or
(b) Operate an aircraft that is equipped with an anticollision light system, unless it has lighted anticollision lights. However, the anticollision lights need not be lighted when the pilot-in-command determines that, because of operating conditions, it would be in the interest of safety to turn the lights off.

www.airweb.faa.gov...

FAA FAR 23.1401, 25.1401, 27.1401, 29.1401

Anticollision light system.

[(a) General. The airplane must have an anticollision light system that--]
(1) Consists of one or more approved anticollision lights located so that their light will not impair the flight crewmembers' vision or detract from the conspicuity of the position lights; and
(2) Meets the requirements of paragraphs (b) through (f) of this section.
(b) Field of coverage. The system must consist of enough lights to illuminate the vital areas around the airplane, considering the physical configuration and flight characteristics of the airplane. The field of coverage must extend in each direction within at least 75° above and 75° below the horizontal plane of the airplane, except that there may be solid angles of obstructed visibility totaling not more than 0.5 steradians.
(c) Flashing characteristics. The arrangement of the system, that is, the number of light sources, beam width, speed of rotation, and other characteristics, must give an effective flash frequency of not less than 40, nor more than 100, cycles per minute. The effective flash frequency is the frequency at which the airplane's complete anticollision light system is observed from a distance, and applies to each sector of light including any overlaps that exist when the system consists of more than one light source. In overlaps, flash frequencies may exceed 100, but not 180, cycles per minute.
(d) Color. Each anticollision light must be either aviation red or aviation white and must meet the applicable requirements of Sec. 23.1397.
(e) Light intensity. The minimum light intensities in any vertical plane, measured with the red filter (if used) and expressed in terms of "effective" intensities, must meet the requirements of paragraph (f) of this section. The following relation must be assumed:
Ie=;
where:
Ie = effective intensity (candles).
I(t) = instantaneous intensity as a function of time.
t2-t1 = flash time interval (seconds).

Normally, the maximum value of effective intensity is obtained when t2 and t1 are chosen so that the effective intensity is equal to the instantaneous intensity at t2 and t1.
(f) Minimum effective intensities for anticollision lights. Each anticollision light effective intensity must equal or exceed the applicable values in the following table.

www.airweb.faa.gov...

FAA FAR 103.11

Daylight operations.

(a) No person may operate an ultralight vehicle except between the hours of sunrise and sunset.
(b) Notwithstanding paragraph (a) of this section, ultralight vehicles may be operated during the twilight periods 30 minutes before official sunrise and 30 minutes after official sunset or, in Alaska, during the period of civil twilight as defined in the Air Almanac, if:
(1) The vehicle is equipped with an operating anticollision light visible for at least 3 statute miles; and
(2) All operations are conducted in uncontrolled airspace.

www.airweb.faa.gov...

FAA FAR 23.1397

Color specifications.

Each position light color must have the applicable International Commission on Illumination chromaticity coordinates as follows:
(a) Aviation red--
"y" is not greater than 0.335; and
"z" is not greater than 0.002.
(b) Aviation green--
"x" is not greater than 0.440-0.320 y;
"x" is not greater than y -0.170; and
"y" is not less than 0.390-0.170 x.
(c) Aviation white--
"x" is not less than 0.300 and not greater than 0.540;
"y" is not less than "x-0.040" or "y0-0.010", whichever is the smaller; and
"y" is not greater than "x+0.020" nor "0.636-0.400 x";
Where "y0" is the "y" coordinate of the Planckian radiator for the value of "x" considered.

www.airweb.faa.gov...

FAA FAR 23.1385

Position light system installation.

(a) General. Each part of each position light system must meet the applicable requirements of this section and each system as a whole must meet the requirements of Secs. 23.1387 through 23.1397.
(b) Left and right position lights. Left and right position lights must consist of a red and a green light spaced laterally as far apart as practicable and installed on the airplane such that, with the airplane in the normal flying position, the red light is on the left side and the green light is on the right side.
(c) Rear position light. The rear position light must be a white light mounted as far aft as practicable on the tail or on each wing tip.
(d) Light covers and color filters. Each light cover or color filter must be at least flame resistant and may not change color or shape or lose any appreciable light transmission during normal use.

www.airweb.faa.gov...

I hope that helps!

reply to post by Ionized


When you say air craft did it look like an airplane? What did it sound like?

Were they possibly an aircraft's landing lights? If they were that bright they might have been blocking out your view of the strobes.... but, umm, the aircraft was producing some sound, right?

Conditions: Clear night. The sun had set, the horizon was still multi-colored to the west but fading quickly, could see stars in the sky.

Activity: I was being attentive to the sky that night for some reason, the sunset was cool to watch, and I used to be into astronomy, so I kept watching the stars for a while after. I know the difference between satellites, stars, planets, etc. I saw a few satellites move across the sky. I then saw one object that was moving like a satellite where you would normally see them, but this object slowed and then got smaller as if it had changed to tangential trajectory away from the planet. That really perked my interest so I kept watching for some time.

About 20 minutes later I saw a craft coming straight towards land off of Lake Michigan, heading east (I live in a lakeside town.) It was moving much faster than any of the smaller planes I've seen in this area (we only have a small airport.) It seemed to be at the same height as the small airplanes I’ve seen around here. 2 distinguishable features, other than its higher velocity, were:

1) No sound - I opened the window as I saw it coming. It flew nearly straight overhead and to the left of my house. Like I said it was up high enough like a small prop plane would be but I heard nothing. I was a sound designer at one time and I am trained to listen, however I didn't hear any sound that would be associated with an aircraft, only heard the nighttime ambience. At the height it was I should have heard something even if it was a quiet jet.

2) The lights - No strobes. It had an array of six constant intensity white lights, two rows of three each. As far as I could tell during the time I saw it, the two rows appeared to be separated by the same distance as the lights on each row were, making it look like a rectangular grid.

Some things that prevented me from seeing clearly the shape of the craft:
The 6 white lights were bright enough to make the eye focus towards them. Lack of any other solid or strobe light source made it difficult to distinguish any shape. I saw a black outline that was much larger than the array of lights, but against the dark sky the only contrast was the stars it was blocking out as it moved so it was hard to discern a shape other than to say it seemed oval/rectangular. I don't believe the lights were simply so bright that I couldn't see strobes, the black outline was big enough that if there were strobes they would have been positioned away from the grid of white lights, which appeared to be at the center of the craft. One way to tell an airplane is the position of the strobes and other lights around the plane. This craft had none of that.

I don't purport to know what I saw that night. In the true sense it was unidentified and strange. Had it made sound, came in a little slower, and had something other than only 6 white lights, I would have written it off as some strange jet. Whether or not it was driven by terrestrial or extra-terrestrial beings doesn't matter much to me (both of which, being an ex-astrophysicist, I strongly believe in.) It was nothing I had seen before and that prompted me to make this thread asking about the lighting laws. From what I could tell, it was breaking them.