Just been flying a new A320 with Sharklets.
"And... as for having the strobes installed on the leading edge, it's a legal requirement. 110 degree field of view for the wing tip strobes, forward facing, etc. etc.. It was there in one of the ICAO annexes or CAR's. I did study this a long time back in ground school... can't remember the exact numbers, though."
There is no requirement that I know of for "Strobes" to be visible from leading edge nor that they cover a field of 110º since no position information is gleaned from them. In fact there there is no requirement that I know of to have them switched on. There is a requirement to have either an anti-collision beacon or strobes but if you have the beacon you do not need strobes.
There is a requirement for Port, Starboard and Tail Navigation lights to be on from 30 mins before sunset to 30mins after sunrise (if memory serves me and this is FAA). The requirement for the Port and Starboard Naveigation lights is from Straight ahead to 110º either side. On the A320 with Sharklets the the Port Nav light is visible not only from the flight deck but a good 10º to the right of the centre line and vice versa for the starboard. I would have thought this was actually contrary to certification requirments.
The following is extracted from FAR Part 25-(God knows where it is now under EASA Acceptible Means of Compliance) but I doubt there is a variation in this as it is probably maritime law and certainly under what was UK rules of the air.
FAA Part 25 States:
§ 25.1385 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 §§ 25.1387 through 25.1397.
(b) Forward position lights. Forward position lights must consist of a red and a green light spaced laterally as far apart as practicable and installed forward on the airplane so 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. Each light must be approved.
(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, and must be approved.
(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.
[Doc. No. 5066, 29 FR 18291, Dec. 24, 1964, as amended by Amdt. 25-38, 41 FR 55468, Dec. 20, 1976]
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§ 25.1387 Position light system dihedral angles.
(a) Except as provided in paragraph (e) of this section, each forward and rear position light must, as installed, show unbroken light within the dihedral angles described in this section.
(b) Dihedral angle L (left) is formed by two intersecting vertical planes, the first parallel to the longitudinal axis of the airplane, and the other at 110 degrees to the left of the first, as viewed when looking forward along the longitudinal axis.
(c) Dihedral angle R (right) is formed by two intersecting vertical planes, the first parallel to the longitudinal axis of the airplane, and the other at 110 degrees to the right of the first, as viewed when looking forward along the longitudinal axis.
(d) Dihedral angle A (aft) is formed by two intersecting vertical planes making angles of 70 degrees to the right and to the left, respectively, to a vertical plane passing through the longitudinal axis, as viewed when looking aft along the longitudinal axis.
(e) If the rear position light, when mounted as far aft as practicable in accordance with § 25.1385(c), cannot show unbroken light within dihedral angle A (as defined in paragraph (d) of this section), a solid angle or angles of obstructed visibility totaling not more than 0.04 steradians is allowable within that dihedral angle, if such solid angle is within a cone whose apex is at the rear position light and whose elements make an angle of 30° with a vertical line passing through the rear position light.
[Doc. No. 5066, 29 FR 18291, Dec. 24, 1964, as amended by Amdt. 25-30, 36 FR 21278, Nov. 5, 1971]
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§ 25.1389 Position light distribution and intensities.
(a) General. The intensities prescribed in this section must be provided by new equipment with light covers and color filters in place. Intensities must be determined with the light source operating at a steady value equal to the average luminous output of the source at the normal operating voltage of the airplane. The light distribution and intensity of each position light must meet the requirements of paragraph (b) of this section.
(b) Forward and rear position lights. The light distribution and intensities of forward and rear position lights must be expressed in terms of minimum intensities in the horizontal plane, minimum intensities in any vertical plane, and maximum intensities in overlapping beams, within dihedral angles L, R, and A, and must meet the following requirements:
(1) Intensities in the horizontal plane. Each intensity in the horizontal plane (the plane containing the longitudinal axis of the airplane and perpendicular to the plane of symmetry of the airplane) must equal or exceed the values in § 25.1391.
(2) Intensities in any vertical plane. Each intensity in any vertical plane (the plane perpendicular to the horizontal plane) must equal or exceed the appropriate value in § 25.1393, where I is the minimum intensity prescribed in § 25.1391 for the corresponding angles in the horizontal plane.
(3) Intensities in overlaps between adjacent signals. No intensity in any overlap between adjacent signals may exceed the values given in § 25.1395, except that higher intensities in overlaps may be used with main beam intensities substantially greater than the minima specified in §§ 25.1391 and 25.1393 if the overlap intensities in relation to the main beam intensities do not adversely affect signal clarity. When the peak intensity of the forward position lights is more than 100 candles, the maximum overlap intensities between them may exceed the values given in § 25.1395 if the overlap intensity in Area A is not more than 10 percent of peak position light intensity and the overlap intensity in Area B is not greater than 2.5 percent of peak position light intensity.
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§ 25.1391 Minimum intensities in the horizontal plane of forward and rear position lights.
Each position light intensity must equal or exceed the applicable values in the following table:
Dihedral angle (light included)
Angle from right or left of longitudinal axis, measured from dead ahead
Intensity (candles)
LandR(forward red and green)
0° to 10°
10° to 20°
20° to 110°
40
30
5
A (rear white)
110° to 180°
20
I have never read of any legal requirment for the strobes to be on the leading edge with a 110º field of view. A lot of aircraft have the strobes mounted on the actual wingtip behind the leading edge and many aircraft also have the Navigation lights mounted on the actual wingtip but behind the leading edge this effectively providing the cut off for straight ahead. So long as they are visible from straight ahead back round 110º they are OK.
Regarding the Anti-Collision Light system, FAR 25 again states:
§ 25.1401 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 crew's 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 degrees above and 75 degrees below the horizontal plane of the airplane, except that a solid angle or angles of obstructed visibility totaling not more than 0.03 steradians is allowable within a solid angle equal to 0.15 steradians centered about the longitudinal axis in the rearward direction.
(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 § 25.1397.
Link to the FAA page:
eCFR ? Code of Federal Regulations
The main point is the Nav lights should not really be directly visible from the flight deck which they are on the sharklet A320 and the strobes should certainly not be visible and flashing into the flight deck.
To say "Airbus are aware of this issue" is just flabbergasting. How the hell did they get an STC or new C of A for these sharklets with lights installed in this manner? IMHO this is a real
up.