Glide slope vs Glidepath (EASA)
Thread Starter
Join Date: Aug 2002
Location: U.K
Posts: 26
Likes: 0
Received 0 Likes
on
0 Posts
Glide slope vs Glidepath (EASA)
Hi,
is anyone aware of a difference in legal definition between glide slope and glidepath. Anecdotally glide slope is the approach aid and glide path is trajectory, but is this referenced anywhere?
Many thanks
is anyone aware of a difference in legal definition between glide slope and glidepath. Anecdotally glide slope is the approach aid and glide path is trajectory, but is this referenced anywhere?
Many thanks
Join Date: Nov 2005
Location: Zulu Time Zone
Posts: 730
Likes: 0
Received 0 Likes
on
0 Posts
is anyone aware of a difference in legal definition between glide slope and glidepath
GLIDEPATH−
(See GLIDESLOPE.)
GLIDEPATH [ICAO]− A descent profile determined
for vertical guidance during a final approach.
GLIDESLOPE− Provides vertical guidance for
aircraft during approach and landing.
(See GLIDESLOPE.)
GLIDEPATH [ICAO]− A descent profile determined
for vertical guidance during a final approach.
GLIDESLOPE− Provides vertical guidance for
aircraft during approach and landing.
Overeasy
Interesting question I’d never considered. Maybe it’s just different terms for exactly the same thing like landing gear and undercarriage or afterburner and reheat?
Also, your post got me thinking why the word “glide” is used? The BA B777 that tried that at LHR was very lucky to make the airport!
Interesting question I’d never considered. Maybe it’s just different terms for exactly the same thing like landing gear and undercarriage or afterburner and reheat?
Also, your post got me thinking why the word “glide” is used? The BA B777 that tried that at LHR was very lucky to make the airport!
Join Date: May 2007
Location: UK
Age: 40
Posts: 115
Likes: 0
Received 0 Likes
on
0 Posts
Glideslope is associated with ICAO precision approaches, so normal ILS but also MLS or PAR. Since the advent of RNP you now have another type of vertical guidance but it didn't meet the ICAO criteria of precision approach so the term glidepath was used instead. Glidepath should only be seen in the civilian world when associated with ICAO classically classified non precision approach systems but still 3D approaches. Such as LPV, LNAV/VNAV, RNP AR APHC and the avionic specific LP+V, LNAV+V.
Slope is that required, normally ground referenced; e.g.ILS GP is three deg.
Path is that being flown (or required) by the aircraft; aircraft referenced; e.g. flightpath is 4 deg, descending.
But PAPI = path indicator, whereas previously VASI = slope indicator !!!
Why the 'legal' tag ? Actions may be legal, but not necessarily safe.
Path is that being flown (or required) by the aircraft; aircraft referenced; e.g. flightpath is 4 deg, descending.
But PAPI = path indicator, whereas previously VASI = slope indicator !!!
Why the 'legal' tag ? Actions may be legal, but not necessarily safe.
Join Date: Dec 2014
Location: Uk
Posts: 4
Likes: 0
Received 0 Likes
on
0 Posts
Glideslope is associated with ICAO precision approaches, so normal ILS but also MLS or PAR. Since the advent of RNP you now have another type of vertical guidance but it didn't meet the ICAO criteria of precision approach so the term glidepath was used instead. Glidepath should only be seen in the civilian world when associated with ICAO classically classified non precision approach systems but still 3D approaches. Such as LPV, LNAV/VNAV, RNP AR APHC and the avionic specific LP+V, LNAV+V.
Join Date: Nov 2015
Location: Paisley, Florida USA
Posts: 289
Likes: 0
Received 0 Likes
on
0 Posts
Slope is that required, normally ground referenced; e.g.ILS GP is three deg.
Path is that being flown (or required) by the aircraft; aircraft referenced; e.g. flightpath is 4 deg, descending.
But PAPI = path indicator, whereas previously VASI = slope indicator !!!
Why the 'legal' tag ? Actions may be legal, but not necessarily safe.
Path is that being flown (or required) by the aircraft; aircraft referenced; e.g. flightpath is 4 deg, descending.
But PAPI = path indicator, whereas previously VASI = slope indicator !!!
Why the 'legal' tag ? Actions may be legal, but not necessarily safe.
Cheers,
Grog
Join Date: Mar 2001
Location: I wouldn't know.
Posts: 4,497
Likes: 0
Received 0 Likes
on
0 Posts
As Sleepybhudda mentions probably the difference between precision and non precision but yet still vertically defined path. Back when i was still on the 737 it showed G/P on the FMA in an IAN non-precision approach (FMC computed glidepath) and G/S for precision approaches (ILS/GLS). Dunno if EASA uses something similar, but it does make sense in a way. Sadly now on the bus we do not have something as easy to use as IAN, although i hear the newer ones do have it.
Join Date: Mar 2006
Location: USA
Posts: 2,515
Likes: 0
Received 0 Likes
on
0 Posts
I’ve always treated glide path as an RNAV glideslope, in much the same way I treat final course as an RNAV localiser.
How does it go? They're the same thing. Just different.
How does it go? They're the same thing. Just different.
Thread Starter
Join Date: Aug 2002
Location: U.K
Posts: 26
Likes: 0
Received 0 Likes
on
0 Posts
Hi All,
Thanks very much for responses. Reason I ask is that steep approach criteria specifies a glide slope of 4.5 deg or more. If manoeuvring in a visual circle to land requires a glide path on the final approach of more than 4.5 degrees path, does this necessitate a steep approach approval for the Operator, Aircraft and crew.
Thanks very much for responses. Reason I ask is that steep approach criteria specifies a glide slope of 4.5 deg or more. If manoeuvring in a visual circle to land requires a glide path on the final approach of more than 4.5 degrees path, does this necessitate a steep approach approval for the Operator, Aircraft and crew.
Join Date: Apr 2010
Location: IRS NAV ONLY
Posts: 1,230
Likes: 0
Received 0 Likes
on
0 Posts
If manoeuvring in a visual circle to land requires a glide path on the final approach of more than 4.5 degrees path, does this necessitate a steep approach approval for the Operator, Aircraft and crew.
From dated memory, the steep approach criteria evolved in two areas; an approach to an airport, without landing from a steep approach procedure vs approaching a runway to land, maintaining the approach angle.
Examples were Lugano, where the approach was into a valley, aiming short of the runway which required the aircraft to transition to a lower - PAPI defined final approach to land (GA terrain issue).
These operations may not require special aircraft or crew approval, depending on the type of operation and regulator (country). Obviously the aircraft had to be capable of flying the initial approach 'path', but not necessarily landing from a steep 'angle'.
Alternatively London City involves landing directly from the steep approach and requires full approval, particularly that the aircraft could maintain the required glide path (ILS or PAPI) in all conditions and be flared from the steeper angle.
Thus if a circle-to-land procedure involves a landing flare directly from a steep final approach, then both crew and aircraft should be approved, but check type of operation and regulation, e.g. USA part 23 not required, part 25 would be; EASA, probably all commercial operations.
There could be wriggle-room for a visual only final approach and need to meet icing configuration / thrust requirements or not, but the flare could still be limiting.
World example - Aspen used to allow approach to circle, but then Nav aids change / improve.
Examples were Lugano, where the approach was into a valley, aiming short of the runway which required the aircraft to transition to a lower - PAPI defined final approach to land (GA terrain issue).
These operations may not require special aircraft or crew approval, depending on the type of operation and regulator (country). Obviously the aircraft had to be capable of flying the initial approach 'path', but not necessarily landing from a steep 'angle'.
Alternatively London City involves landing directly from the steep approach and requires full approval, particularly that the aircraft could maintain the required glide path (ILS or PAPI) in all conditions and be flared from the steeper angle.
Thus if a circle-to-land procedure involves a landing flare directly from a steep final approach, then both crew and aircraft should be approved, but check type of operation and regulation, e.g. USA part 23 not required, part 25 would be; EASA, probably all commercial operations.
There could be wriggle-room for a visual only final approach and need to meet icing configuration / thrust requirements or not, but the flare could still be limiting.
World example - Aspen used to allow approach to circle, but then Nav aids change / improve.
Thread Starter
Join Date: Aug 2002
Location: U.K
Posts: 26
Likes: 0
Received 0 Likes
on
0 Posts
Hi,
Yes I think that is where it is at. The airport in question is Annecy LFLP. Interestingly there seems to be no requirement from the airport to be steep approach capable to use RWY 22 for landing and requires no special training if the WX is better than 3,000 and 5k. The PAPI glidepath set to 5.3 deg. Steep approach definition refers to a glideslope specifically not glide path hence my original question.
Yes I think that is where it is at. The airport in question is Annecy LFLP. Interestingly there seems to be no requirement from the airport to be steep approach capable to use RWY 22 for landing and requires no special training if the WX is better than 3,000 and 5k. The PAPI glidepath set to 5.3 deg. Steep approach definition refers to a glideslope specifically not glide path hence my original question.