6 ms·

Standard aviation approach glideslope is 3degrees. Usually approximated at a 1:60 rule. So every mile is 300 feet. 1 NM = 6076ft tan 3deg = 0.0524 So 318.4f

Standard aviation approach glideslope is 3degrees. Usually approximated at a 1:60 rule. So every mile is 300 feet. 1 NM = 6076ft tan 3deg = 0.0524 So 318.4ft/NM, or 276.68ft/statute mile. So at 2 miles(nautical) out an aircraft ON the glideslope is at approx 600ft. A GA pilot flying VFR may be a little off. 5 miles doesn't seem a terribly bad exclusion zone here.

sathackr 11y ago
Thank you -- information I didn't have. Seems this, as well as the 400ft rule, is inline with the FAA's requirements for determining if an object is a hazard to the navigable airspace (Anything over 499ft, and -- within 3NM of the airport, anything over 200ft, adding 100ft for each NM in excess of 3) [1] But, for the most part, this glideslope should extend only in the direction of the runways, correct? AFAIK There shouldn't be any aircraft approaching the airport below 500ft at a significant angle from a runway? For the general masses, I can understand the FAA's reluctance to have everyone work out the angles of runways, glideslopes, etc... to see if they can fly and how high. My main complaint is that DJI firmware won't let you leave the ground, even if you have worked out an agreement with the airport. For someone that lives near an airport, this pretty much grounds them. [1] http://www.ecfr.gov/cgi-bin/text-idx?c=ecfr&rgn=div5&view=text&node=14:2.0.1.2.9&idno=14#se14.2.77_117 http://www.ecfr.gov/cgi-bin/text-idx?c=ecfr&rgn=div5&view=te...
- anexprogrammer 11y ago
  Firmware seems overly restrictive - I thought drone rules were only to ask ATC if inside controlled airspace. Unless there's temporary airspace restrictions you should be OK. Runway is typically set depending on the prevailing winds. Obviously if it's a single runway GA airport you only get two choices. If it's two or three runway, the active runway can change any time with the wind direction, and the pattern adjusts. There's a few other factors that may influence the exclusion. First is the VFR GA circuit (pattern) - which is 1000ft agl. You fly a rectangle - parallel to the runway, turn left, left again and you're on approach. You want as little as possible around you as it's a period of high workload doing landing checks, and other GA pilots will be joining and leaving the circuit, usually from the side. You'll be well outside the threshold for most of it. You're already scanning for potential impacts, but the traffic is arranged such that nothing should be coming at you, or from below you - they're the really difficult ones to spot. If the weather is crap and the cloudbase lowers you'll do bad weather circuits - perhaps down to 500ft. You;ll be a lot tighter in to the field though. Second, you'll sometimes extend circuit, usually downwind, to avoid commercial, military or heavy traffic (737 747 etc). ATC will sometimes (rarely) send you off in a random direction to keep separation with commercial or a heavy. You should still be circuit height agl though. Commercial IFR stuff won't be mucking about in the pattern at 1000ft agl of course. I doubt many drones are big enough to show on radar. So a couple of miles out there shouldn't be anything at 500ft agl to the sides of the runway, unless something something exceptional is going on. If it's a GA airfield like some of the more rural unmanned US ones, where you're the only thing in the sky, it's stupidly restrictive. If it's the airfield I learnt to fly at, with many aircraft in constant movement and two heleports, I don't want any more dots to scan for thanks very much. It's probably more dangerous in whichever local area the instructors use to practice engine failures and emergency landings. Often a local beach or farm fields near the airfield, and usually uncontrolled airspace. I'm guessing the rules are to try and limit things in the sky near airfields to those who know what they're doing, contact ATC, read NOTAMs and METARs, not scaring the students on their first solo and what have you.

sathackr 11y ago

Thank you -- information I didn't have. Seems this, as well as the 400ft rule, is inline with the FAA's requirements for determining if an object is a hazard to the navigable airspace (Anything over 499ft, and -- within 3NM of the airport, anything over 200ft, adding 100ft for each NM in excess of 3) [1] But, for the most part, this glideslope should extend only in the direction of the runways, correct? AFAIK There shouldn't be any aircraft approaching the airport below 500ft at a significant angle from a runway? For the general masses, I can understand the FAA's reluctance to have everyone work out the angles of runways, glideslopes, etc... to see if they can fly and how high. My main complaint is that DJI firmware won't let you leave the ground, even if you have worked out an agreement with the airport. For someone that lives near an airport, this pretty much grounds them. [1] http://www.ecfr.gov/cgi-bin/text-idx?c=ecfr&rgn=div5&view=text&node=14:2.0.1.2.9&idno=14#se14.2.77_117 http://www.ecfr.gov/cgi-bin/text-idx?c=ecfr&rgn=div5&view=te...

anexprogrammer 11y ago
Firmware seems overly restrictive - I thought drone rules were only to ask ATC if inside controlled airspace. Unless there's temporary airspace restrictions you should be OK. Runway is typically set depending on the prevailing winds. Obviously if it's a single runway GA airport you only get two choices. If it's two or three runway, the active runway can change any time with the wind direction, and the pattern adjusts. There's a few other factors that may influence the exclusion. First is the VFR GA circuit (pattern) - which is 1000ft agl. You fly a rectangle - parallel to the runway, turn left, left again and you're on approach. You want as little as possible around you as it's a period of high workload doing landing checks, and other GA pilots will be joining and leaving the circuit, usually from the side. You'll be well outside the threshold for most of it. You're already scanning for potential impacts, but the traffic is arranged such that nothing should be coming at you, or from below you - they're the really difficult ones to spot. If the weather is crap and the cloudbase lowers you'll do bad weather circuits - perhaps down to 500ft. You;ll be a lot tighter in to the field though. Second, you'll sometimes extend circuit, usually downwind, to avoid commercial, military or heavy traffic (737 747 etc). ATC will sometimes (rarely) send you off in a random direction to keep separation with commercial or a heavy. You should still be circuit height agl though. Commercial IFR stuff won't be mucking about in the pattern at 1000ft agl of course. I doubt many drones are big enough to show on radar. So a couple of miles out there shouldn't be anything at 500ft agl to the sides of the runway, unless something something exceptional is going on. If it's a GA airfield like some of the more rural unmanned US ones, where you're the only thing in the sky, it's stupidly restrictive. If it's the airfield I learnt to fly at, with many aircraft in constant movement and two heleports, I don't want any more dots to scan for thanks very much. It's probably more dangerous in whichever local area the instructors use to practice engine failures and emergency landings. Often a local beach or farm fields near the airfield, and usually uncontrolled airspace. I'm guessing the rules are to try and limit things in the sky near airfields to those who know what they're doing, contact ATC, read NOTAMs and METARs, not scaring the students on their first solo and what have you.