Originally Posted by
Fris B. Fairing
The question was; How can it improve cockpit visibility by eliminating four windows that were there as original equipment? When they were converting DC-4s to tankers they would often install an eyebrow window for the very purpose later described by Checkboard.
Originally Posted by
Checkboard
I flew 737s with eyebrows out of Perth. They were very useful in visual circuits and circling. On a base turn to the otherside (i.e. flying left seat and turning right or vise versa) the threshold is nicely visible in the eyebrow window.
The required visual field is laid out in §25.773, in very little detail, and amplified in AC 25.773-1. It is of interest on occasions, when near miss or un near misses (hits) happen. My old P3 and the Hercules as well had lots of glass up top, and the P3 was also good for a suntan but not much else, then again we were often well over 30 bank, up to 70 degree for some tac stuff, and that could be dealing with a single light source on a dark night in the middle of nowhere. The eyebrows were not overly useful even in the low level circuit. It's an interesting discussion, not related to the incident at hand, but the perception of a pill box visual for the B737 has come up on a number of bad events, and does not seem to really hold much water. (LAT's got the water tho...). I'm doing a test in a B737 next week, and also in another aircraft with eyebrows, and will take some snaps of the cross cockpit FOV, I am surprised that the B737 eyebrow actually gives meaningful cues to a visual circuit, but it would be interesting to see that. It's a simple process to determine the FOV from the design eye point, and then work back to see if there is pilot assistance from an expanded criteria. The A350 has a larger FOV than the vanilla rule and the GM on the subject, maybe that helps drive around the pattern. Large aircraft visual patterns are replete with examples of the drivers getting down into the weeds for various reasons, many the "100" "50" "40" "30" calls happening without a runway in front are the big cues, or the fish nets caught on the windscreen wipers...