Hi Doofer, Good stuff. Your explanations were clear and easy to understand, and your graphics of the different categories will make them easier to remember.
I am finding that your videos are very informative and can really help the new ATC or a new pilot. There was a few things that I think you should go back and look at. ILS IIIc - the airport would not close. In order to be Cat IIIc the airport and the airplane HAVE to be able to Land AND Taxi to the gate automatically. Also, anything over Cat I ILS- the plane and the ILS equipment must be certified to do suck approach (as you mention) but also the crew must go through special training in order to be compliant with this kind of approach. I hope this helps clear up some confusion. Otherwise this video is spot on.
Hi Doofer911, What is the difference between Decision height (DH) and Runway visual range (RVR)? If you cannot see the runway from the RVR distance, should you go around too?
I'm not sure I understand the third column. Is it column DA + Runway visual range? Or DA or Runway visual range are conditions for flying cat 1, 2, and 3?
Hi, I would like to ask two questions: 1. is autoland allowed only on ILS cat IIIc or on any cat III? Maybe that's why it's devided? 2. What's the difference between DH and MDA? Great channel btw! ;)
1. I think Autoland is allowed on any CAT III equipped runway but the aircraft has to have the equipment to work with CAT III ILS as well. 2. They're both essentially the same thing but I THINK... DH is the height above ground, MDA is the height above Sea Level
pedeiksz hi ! DH or DA (Decision Heigt or Decision altitude, the only difference between them is the DA is referenced to mean sea level whereas DH is referenced to the threshold elevation) are only used for precision approaches such as ILS. When you pass through DA (or DH), if you see the runway you can continue the approach, if not a go around must be initiated immediatly ! The MDA (Minimum Descent Altitude) is used for non precision approaches (LOC, VOR/DME , NDB, RNAV...). This is the minimum altitude you can reach before having runway in sight. You fly the approach's descent profile until the MDA, and when you reach it, you level fly at MDA. The decision to make the go around is done at the MAPt (Missed Approach Point, try to find it on a VOR/DME final approch charts). If you see the rwy before passing the MAPt, you continue the descent towards airport ! (you dont have to wait for the MAPt to start descending). If, when you reach the MAPt, you dont have the rwy in sight yet, you go around ! Of course, if you see the runway before passing MDA, you dont have to level fly ! Hope i've been clear enough ;)
Hi Doofer911, thanks for this explanatory video. I understand decision height (DH) for ILS CAT III is between 0-100ft. What would be the OCH for ILS CAT III? Thank you
OCH = Obstacle Clearance Height. That will be a height unique to different airports, depending on the obstacles around the airport and it's runway(s). You'll likely find the OCH on approach charts for an airport.
There isn't any Decision Height for a Visual Approach. Visual Approaches by their definition require the pilot to be focused on the runway and PAPI/VASI lights during the approach and not looking at instruments in the cockpit. Therefore Visual Approaches are only conduced when there is very good visibility.
I was watching a video today where a Phenom corporate jet was executing an instrument approach. The airport's: 1.) DH = 1,100 ft. 2.) Minimums = 300 ft. The video showed him passing well below 1,100 ft. with no visual sighting of the runway. He continued descending until just before reaching Minimums (300 ft.) the runway appeared. This confused me as I thought Decision Height (DH) would be more important. Does anyone know which is more important, DH or Minimums?
I asked a real Flight Instructor about this. In the UK, all our Instrument Procedure Charts give Decision Heights as minimum altitudes. Decision Height is the legal minimum height. "Minimums" are normally an operator's/airline's minimum height. So for example on an approach.... The Decision Height could be 300ft which is legally, the lowest altitude a plane should descend to. An Airline may choose to set their Minimums to Decision Height + 50ft (350ft in this example) and hold their pilots to fly to the Airline's Standard Operating Procedures. As I said, this is the case in the UK, it could be different in other countries.
Just saw this video and your comment, even its 2 years ago i want to add someting: As you mention decision HEIGHT: This would mean the distance between ground level and the height in the air. I never heard someone using height in this regard, its always altitude with is the distance between MSL and the point in the air. Your given example could be totally fine when the aerodrome hat a field elevation of 800ft because then DH of 1100ft and Minimums of 300ft mean the same. Normally Decision Altitude is the proper term used and the word "minimums" is used interchangeably. It comes from "minimums" is the general term for the visibility and ceiling for any instrument approach. For non precision approaches its Minimum Decent Altitude and for precision approaches its Decision Altitude.
Good video as always. But how do pilots know the runway visual range? Determine by their own eys? From ATC? And, if I fly to a Category 1 airports but ranway visual range is less than 1800ft, is it mean that I cannot land my aircraft? Or there are some special regulations? Some people in fb told me that in that case I will need to use autoland, is that true? Thanks!!!
King Lim Pang Cat 1 ILS is more sensitive to external disturbance. For example if a maintenance vehicle drives past the end of the runway where the ILS antennas sit, it can interrupt the signal to the plane. Also, only certain aircraft can autoland. They usually need complex computers and instruments to be installed.
It is no longer called Decision Height and the fact that you didn't know this means you are not a current instrument rated pilot. It changed to Decision Altitude for Category 1 approaches many years ago because those approaches have an Altitude where the pilot must make a decision to continue the approach or go around. Cat ll approaches use a radar altimeter, and minimums are around 100 feet radar altitude, which is called Decision Height because the radar altimeter measures height above the ground. And THERE IS NO SUCH THING AS A DECISION HEIGHT/ALTITUDE FOR CATs llla, b, and c approaches as the ceiling will almost always be zero. We use Runway Visual Range, or RVR solely as our minimums, and not a DA. For Cat llla it is RVR 700 feet, For Cat lllb, it is RVR 300 feet, and for Cat lllc there are no minimums as you can land zero zero if the airplane and pilot are qualified to do so. Look at the ILS Approach for Denver's Runway 34R for an example of a Cat lllc approach. All Cat lll approaches are autoland only as the autopilot must fly the approach and make the landing. You are not qualified to post a tutorial on ILS approaches. Do your homework next time or talk to an airline pilot like me to learn all about the different categories for ILS approaches.
![ILS Categories - [Learn How To Choose The Right ILS Procedure When The Visibility Is Not Great!]](/img/n.gif)
Hi Doofer, Good stuff. Your explanations were clear and easy to understand, and your graphics of the different categories will make them easier to remember.
Amazing video, i will never forget this wonderful experience❤❤
I am finding that your videos are very informative and can really help the new ATC or a new pilot. There was a few things that I think you should go back and look at.
ILS IIIc - the airport would not close. In order to be Cat IIIc the airport and the airplane HAVE to be able to Land AND Taxi to the gate automatically.
Also, anything over Cat I ILS- the plane and the ILS equipment must be certified to do suck approach (as you mention) but also the crew must go through special training in order to be compliant with this kind of approach.
I hope this helps clear up some confusion. Otherwise this video is spot on.
Ah ok, am I right in thinking that the technology to taxi automatically doesn't exist yet?
No, ILN, ATL, SFO, OAK, ORD
The only thing to suggest is to talk about the difference between decision altitude DA and decision height DH.
Excellent video. Thanks
Hi Doofer911, What is the difference between Decision height (DH) and Runway visual range (RVR)? If you cannot see the runway from the RVR distance, should you go around too?
Yes, I think if the RVR is too low, then the airport will close the runway until the visibility improves.
I'm not sure I understand the third column. Is it column DA + Runway visual range? Or DA or Runway visual range are conditions for flying cat 1, 2, and 3?
Very well explained, thank you very much
You're welcome, thanks very much for watching!
Hi, I would like to ask two questions:
1. is autoland allowed only on ILS cat IIIc or on any cat III? Maybe that's why it's devided?
2. What's the difference between DH and MDA?
Great channel btw! ;)
1. I think Autoland is allowed on any CAT III equipped runway but the aircraft has to have the equipment to work with CAT III ILS as well.
2. They're both essentially the same thing but I THINK... DH is the height above ground, MDA is the height above Sea Level
pedeiksz hi ! DH or DA (Decision Heigt or Decision altitude, the only difference between them is the DA is referenced to mean sea level whereas DH is referenced to the threshold elevation) are only used for precision approaches such as ILS. When you pass through DA (or DH), if you see the runway you can continue the approach, if not a go around must be initiated immediatly !
The MDA (Minimum Descent Altitude) is used for non precision approaches (LOC, VOR/DME , NDB, RNAV...). This is the minimum altitude you can reach before having runway in sight.
You fly the approach's descent profile until the MDA, and when you reach it, you level fly at MDA. The decision to make the go around is done at the MAPt (Missed Approach Point, try to find it on a VOR/DME final approch charts). If you see the rwy before passing the MAPt, you continue the descent towards airport ! (you dont have to wait for the MAPt to start descending). If, when you reach the MAPt, you dont have the rwy in sight yet, you go around !
Of course, if you see the runway before passing MDA, you dont have to level fly !
Hope i've been clear enough ;)
Doofer911 MDA is used on NPA based on QNH setting, whila MDH is used for NPA and based on AGL.
What is the difference between ILS Cat III Single and Dual?
Hi Doofer911, thanks for this explanatory video. I understand decision height (DH) for ILS CAT III is between 0-100ft. What would be the OCH for ILS CAT III? Thank you
OCH = Obstacle Clearance Height. That will be a height unique to different airports, depending on the obstacles around the airport and it's runway(s). You'll likely find the OCH on approach charts for an airport.
@@Doofer911 Thanks for the answer!
good tutorial as always ;)
Cheers, glad you liked it!
Thank you very much!!!
Hello Doofer, so if it is a very good clear weather day, can I pilot perform Cat 2 or 3 procedures?
Depends if the runway's ILS system and the aircraft's instruments are complex enough to support those procedures.
On a Visual Approach the Decision Height is 500 ft., right?
There isn't any Decision Height for a Visual Approach. Visual Approaches by their definition require the pilot to be focused on the runway and PAPI/VASI lights during the approach and not looking at instruments in the cockpit. Therefore Visual Approaches are only conduced when there is very good visibility.
I was watching a video today where a Phenom corporate jet was executing an instrument approach. The airport's:
1.) DH = 1,100 ft.
2.) Minimums = 300 ft.
The video showed him passing well below 1,100 ft. with no visual sighting of the runway. He continued descending until just before reaching Minimums (300 ft.) the runway appeared.
This confused me as I thought Decision Height (DH) would be more important.
Does anyone know which is more important, DH or Minimums?
I asked a real Flight Instructor about this. In the UK, all our Instrument Procedure Charts give Decision Heights as minimum altitudes. Decision Height is the legal minimum height. "Minimums" are normally an operator's/airline's minimum height. So for example on an approach.... The Decision Height could be 300ft which is legally, the lowest altitude a plane should descend to. An Airline may choose to set their Minimums to Decision Height + 50ft (350ft in this example) and hold their pilots to fly to the Airline's Standard Operating Procedures. As I said, this is the case in the UK, it could be different in other countries.
Just saw this video and your comment, even its 2 years ago i want to add someting:
As you mention decision HEIGHT: This would mean the distance between ground level and the height in the air. I never heard someone using height in this regard, its always altitude with is the distance between MSL and the point in the air.
Your given example could be totally fine when the aerodrome hat a field elevation of 800ft because then DH of 1100ft and Minimums of 300ft mean the same.
Normally Decision Altitude is the proper term used and the word "minimums" is used interchangeably. It comes from "minimums" is the general term for the visibility and ceiling for any instrument approach. For non precision approaches its Minimum Decent Altitude and for precision approaches its Decision Altitude.
You didn't show where this info is on a chart.
Good video as always.
But how do pilots know the runway visual range? Determine by their own eys? From ATC?
And, if I fly to a Category 1 airports but ranway visual range is less than 1800ft, is it mean that I cannot land my aircraft? Or there are some special regulations? Some people in fb told me that in that case I will need to use autoland, is that true? Thanks!!!
Air Traffic Control + METAR (weather report). I think you can use autoland with a Cat 1 system but it would be dangerous to do.
+Doofer911 Why would it be dangerous? Autoland is not good?
King Lim Pang
Cat 1 ILS is more sensitive to external disturbance. For example if a maintenance vehicle drives past the end of the runway where the ILS antennas sit, it can interrupt the signal to the plane. Also, only certain aircraft can autoland. They usually need complex computers and instruments to be installed.
+Doofer911 Hello. I've got a new question. What is IMC? Thanks!!
Instrument Meteorological Conditions. Try looking some of these questions up online yourself, you will get the answers faster.
I would like to try a visual APPR and LDG for a CAT IIIc ILS
dont do that ! Its not recommended
@@1100BFK i agree. But only in a sim
@VCP / MAS_ pilot lmfao I know just kidding
It is no longer called Decision Height and the fact that you didn't know this means you are not a current instrument rated pilot. It changed to Decision Altitude for Category 1 approaches many years ago because those approaches have an Altitude where the pilot must make a decision to continue the approach or go around. Cat ll approaches use a radar altimeter, and minimums are around 100 feet radar altitude, which is called Decision Height because the radar altimeter measures height above the ground. And THERE IS NO SUCH THING AS A DECISION HEIGHT/ALTITUDE FOR CATs llla, b, and c approaches as the ceiling will almost always be zero. We use Runway Visual Range, or RVR solely as our minimums, and not a DA. For Cat llla it is RVR 700 feet, For Cat lllb, it is RVR 300 feet, and for Cat lllc there are no minimums as you can land zero zero if the airplane and pilot are qualified to do so. Look at the ILS Approach for Denver's Runway 34R for an example of a Cat lllc approach. All Cat lll approaches are autoland only as the autopilot must fly the approach and make the landing. You are not qualified to post a tutorial on ILS approaches. Do your homework next time or talk to an airline pilot like me to learn all about the different categories for ILS approaches.
Check when the video was published.
where did you get this information from ??
The Internet.
This is a very misleading video .
Category 1 -DH 200ft ,RVR 2400ft
Category 2 - DH 100ft ,RVR 1200 ft
Category 3 A - RVR 700ft
The real matter starts at 1:50