Malsua 1,422 Posted March 27, 2017 Can anyone explain to me what the + sign is in front of the floor of the Class B airspace in the first and second rings outside Newark? Also the section of class B over the water around JFK has it as well. The definition is: floors extending "upward from above" have a plus sign. What does that mean? The lower number is the floor, the upper the ceiling..wouldn't they all extend upward? Minus sign in a D/E airspace means SFC to Ceiling but doesn't apply here. I'm working on my Part 107 test and I want to be clear on all this. Quote Share this post Link to post Share on other sites
10X 3,296 Posted March 27, 2017 I'm not sure...I've seen the same definition you have, but I don't understand how 70/+05 differs from 70/05. Unless in the first one, the floor of the Bravo is at 501', and in the second the floor of the Bravo is at 500', but that would seem a meaningless distinction to make. If you don't get an answer here, you'll probably have better luck on one of the pilot boards. https://www.pilotsofamerica.com/community/ and http://www.purpleboard.net/forums/index.php are a couple of free ones. If you are an AOPA member, http://forums.aopa.org/index.php is pretty good. Quote Share this post Link to post Share on other sites
Malsua 1,422 Posted March 27, 2017 I don't understand how 70/+05 differs from 70/05 Exactly. Thanks, so it's not just me. Was hoping someone might just know off the top of their head rather than joining yet another forum. I might anyway, so thanks. Quote Share this post Link to post Share on other sites
jackandjill 683 Posted March 27, 2017 This may help. Just 05 means the controlled airspace starts AT 500. +05 means it starts at 501. http://forums.x-plane.org/index.php?/forums/topic/54180-the-geometry-of-controlled-airspace/ On the New York charts you will see floors of Class B space areas labeled such as “+12”. The 7400.9N description reads “extending upward from above1,200 feet MSL”. As far as I can determine this is the only place where floors do not start at the prescribed altitude. You are in this controlled airspace at 1,201 feet, but not at 1,200. Quote Share this post Link to post Share on other sites
Malsua 1,422 Posted March 27, 2017 This may help. Just 05 means the controlled airspace starts AT 500. +05 means it starts at 501. http://forums.x-plane.org/index.php?/forums/topic/54180-the-geometry-of-controlled-airspace/ On the New York charts you will see floors of Class B space areas labeled such as “+12”. The 7400.9N description reads “extending upward from above1,200 feet MSL”. As far as I can determine this is the only place where floors do not start at the prescribed altitude. You are in this controlled airspace at 1,201 feet, but not at 1,200. Great, thanks. A distinction without a difference. 1 foot is in the margin of measurement error, so it seems like a meaningless complication. Besides, where is this measured? The top of the vertical stabilizer or the lowest part of the belly? Oh noes, the top of the plane is in Bravo but the bottom is going to crash into Charlie's Veil! Quote Share this post Link to post Share on other sites
10X 3,296 Posted March 27, 2017 Great, thanks. A distinction without a difference. 1 foot is in the margin of measurement error, so it seems like a meaningless complication. Besides, where is this measured? The top of the vertical stabilizer or the lowest part of the belly? Oh noes, the top of the plane is in Bravo but the bottom is going to crash into Charlie's Veil! Yep. And for purposes of busting you for an airspace violation, your position is where the radar facility says you are, something that is unknowable to you in the cockpit. It doesn't matter what your altimeter or GPS or Nav radio says, or what your transponder is reporting. One hopes they are all in reasonable agreement, but it's the radar data that matters. Quote Share this post Link to post Share on other sites
weekend_junkie 129 Posted March 28, 2017 1 foot might make a difference for drone, but your standard Cessna would keep it 500ft below anyway. Quote Share this post Link to post Share on other sites
leadunderpressure 52 Posted April 1, 2017 There are areas where you have to thread a 100 ft needle in the area. 1 ft is impossible in a passenger plane. Quote Share this post Link to post Share on other sites