The way I remember flying an inbound course when reverse sensing is saying “I’m the needle the course is the center” and when flying a regular loc “ I am the airplane (center) the course is needle” great video !!
Simplified: 1- look at the OBS/CDI 2- In a normal localizer (non back course) YOU are the CIRCLE in the OBS's center. fly towards the needle. 3- in a back course localizer, YOU are the NEEDLE, fly towards the OBS's CIRCLE. No problem :D Edit: I just realized a lot of people in the comment section actually understood it the same way, I'll keep my comment so that more people could see the idea (poor me thought I came up with an invention of some sort).
I absolutely love your videos, you're a joy to listen to! For any curious engineers out there, this explanation for how an ILS works in incorrect, though you can certainly be forgiven because ISL systems are almost always incorrectly depicted this way. The entire antenna transmits 150/90Hz at the same amplitude, but it phase shifts the sidebands +90/-90 degrees. This creates a magical interference pattern that result in a Difference of the Depth of Modulation (DDM) along the lateral/vertical track. The depicted explanation is called "Received Signal Strength" (RSS) and has problems that would make an ILS unusable. There is a great writeup about it on Aviation StackExchange. As far as what a pilot cares about though, this explanation is more than sufficient.
When I flew commuters (D328s) based out of COS, we served ASP and flew this approach numerous times; sometimes even circle to land on 33. We would brief the “20/20” rule i.e. Cross DBL (Red Table VOR) at FL200, Flaps 20, 200kts GS - if you missed that, you weren’t going to be stable at the latter part of the approach. Thanks for the memories along with the refresher. Safe flights always.
Wow thanks for that great insight! I've always wanted to fly this approach (as do many others) but I'm an East Coast boy and don't make it out there too often!
Another great video! I love that you said “pull” the needle toward you on the back course. That simple word made it so much easier to grasp the concept! Thanks for all that you have been doing with these videos!
Yes, on BC approaches I always thought of the needle as the airplane and the donut as the course/localizer = fly the needle to the course/donut. An HSI solves all the the confusion by setting the course arrow to the front course heading. One more detail is the BC localizer is more sensitive sense the antenna is several thousand feet closer - at the approach end rather than off the departure end of the approach runway.
Absolutely love your videos! I'm preparing for my instrument checkride and have found them to be invaluable. I recently just purchased the commercial course that you offer, and am loving it! So far I'm finding it to be far superior to Sportys or any other ground school I've tried. Thanks for helping me learn so well!
Thanks for this easy to understand explanation, I'm new to the channel but I'll be seeing all tje videos i missed, to catch up, you're doing a great work thanks for the efforts you putting in the contents , my appreciation.
your page is amazing. thank you for answering some of aviations more obscure concepts. I never recieved any teaching with regards to these topics in my training but I know i will need to use them someday soon. I feel a lot more confident now.
The breakdown of the back course at the beginning made sense but that MAP with the dual localizers- yeah, I’m choosing a different approach or waiting for VFR conditions to fly there 😆
First good BC explanation I have seen. One little remark: it is not 437 feet DH AGL, but a MDA of 880 MSL (437 feet AGL), since it is a non precision approach. The BC button provides indeed normal sensing on the HSI when depressed on a BC approach. Thanks for sharing.
Yes thanks for that. It wasn't a decision height but an MDA. This is one of our clues that we're not getting vertical guidance on the approach like on an ILS
Some of the newer OBS instruments have a BC light, which is a green light within the instrument. I’m not sure if that is a function that if you select back course it illuminates and puts the OBS 180° out of phase so that you would fly it like a normal localizer or it’s just a reminder light. On the G 1000 there is a BC button which I believe sets the unit up as a back course. Selecting this button, makes the CDI course selector flip 180° and line up with the opposite runway of the normal ILS. Reverse sensing which is a horrible term and it’s not true, is never experienced when you fly a HSI.
Just had to fly one of these trying to get home in the Simulator. Overcast at 600ft, runway height 300ft. ATC (vatsim) was super confused, and I had one missed approach. Eventually got it. Looking up how to do this properly now. If I'd lost navigational awareness, I would have had to either fly a tailwind approach, or divert to a different airport and drive home (in sim of course).
Two questions here. Does the BC button allow you to fly outbound on a front course only localizer that is using an HSI. Remember the HSI will always point to the inbound course regardless, if you are flying to the localizer 180° from, the approach end or flying outbound opposite the inbound course using the HSI. The ILS 30L at St. Louis downtown has the aircraft on the miss intercepting the localizer and flying outbound back to the hold, which is also the initial approach fix for the inbound.
To avoid reverse sensing indications can you just fly a loc bc by putting in the opposite heading at the top of your obs vor instrument without the need of an hsi?
At 4:31 in the video, you refer to the minimums of the back course approach as "decision height". I disagree with using that term. What you highlight in the video is the minimum descent altitude (MDA), which is 880 feet as referenced on the barometric altimeter. A decision height (DH) is only applicable on a CAT II or CAT III ILS approach and is referenced by a radio altimeter. A decision altitude (DA) is applicable on a CAT I ILS and is referenced on the barometric altimeter. DA and DH differ from an MDA in that on a precision approach, upon reaching the decision point, DA or DH, you must meet the criteria for continuing the approach or execute a missed approach. On a non-precision approach, reaching the MDA is only the lowest altitude you may fly until you either reach the missed approach point or acquire the visual cues necessary to descend from the MDA to make a normal landing. Using the old "dive and drive" technique for a non-precision approach, you might reach the MDA way before the missed approach point. It is perfectly legal to fly along at MDA in this circumstance and wait until reaching the missed approach point, which could be referenced by either time or maybe a DME indication. By calling the MDA on the LOC BC a "decision height", you could introduce a misconception on the part of the student as to which this minimum is called and therefore cause confusion when other concepts are introduced in subsequent training.
If the TO/FROM flag agrees with whether you're flying to/from, chase the needle. If the flag disagrees with how you're flying, then you correct backward. I explained that poorly, it it makes sense to me.
Makes sense to me, if flag says TO, you need to fly TO the deviation on the CDI(needle deflects right, you fly to the right). If flag says FROM, you need to fly away from the deviation (needle goes right, you fly left) I really dislike the Aspen backcourse because it deviates from the norm, even if the norm is somewhat obscure and conveluted
KHQZ uses the back course cause they don't have a ton of money. The tower doesn't have radar and the wonderful controllers just chill up there with binoculars! They're really friendly and funny guys!
Reverse sensing doesn't exist. Turn it 180°, and it will be correct. Because if you factor in which direction you are flying on the CDI, and see it like you're flying downwards, then the needle is right
Im sorry, but isnt it easier to say: this is what you enter into your Nav radios; this is the course to fly on approach (obviously the course opposite the RW with ILS); ignore the vertical guidance; at Mininum do A or B or C and you're good as gold?! I say so because I've watched a number of these backcourse videos and most are tangled in the technicalities rather than simplifying what needs to be done and when to do them. I'm as noob as they come in flying jargon but my interest in Sim flying (particularly MSFS) keeps me interested in these niceties but I need them broken down into digestible bits. This isn't a takedown of your video please - I just need something more bare bones than I'm getting wherever I turn to on UA-cam.
Nope, he means Hz. The carrier is in the 100 and 300 Mhz range for the localizer/glideslope respectively. The tones are 90/150Hz modulated on the carrier.
The way I remember flying an inbound course when reverse sensing is saying “I’m the needle the course is the center” and when flying a regular loc “ I am the airplane (center) the course is needle” great video !!
Haven’t heard that but it’s pretty good. The less mental gymnastics the better!
wow this is very helpful
Simplified:
1- look at the OBS/CDI
2- In a normal localizer (non back course) YOU are the CIRCLE in the OBS's center. fly towards the needle.
3- in a back course localizer, YOU are the NEEDLE, fly towards the OBS's CIRCLE.
No problem :D
Edit: I just realized a lot of people in the comment section actually understood it the same way, I'll keep my comment so that more people could see the idea (poor me thought I came up with an invention of some sort).
Yes, I love this and should probably add this tip in the description
A much easier way to remember!!
LOVE THIS! That “you are the needle” thing on the back course really helped it click for me. Thanks! 🤘🏻
I absolutely love your videos, you're a joy to listen to!
For any curious engineers out there, this explanation for how an ILS works in incorrect, though you can certainly be forgiven because ISL systems are almost always incorrectly depicted this way. The entire antenna transmits 150/90Hz at the same amplitude, but it phase shifts the sidebands +90/-90 degrees. This creates a magical interference pattern that result in a Difference of the Depth of Modulation (DDM) along the lateral/vertical track. The depicted explanation is called "Received Signal Strength" (RSS) and has problems that would make an ILS unusable. There is a great writeup about it on Aviation StackExchange. As far as what a pilot cares about though, this explanation is more than sufficient.
When I flew commuters (D328s) based out of COS, we served ASP and flew this approach numerous times; sometimes even circle to land on 33. We would brief the “20/20” rule i.e. Cross DBL (Red Table VOR) at FL200, Flaps 20, 200kts GS - if you missed that, you weren’t going to be stable at the latter part of the approach. Thanks for the memories along with the refresher.
Safe flights always.
Wow thanks for that great insight! I've always wanted to fly this approach (as do many others) but I'm an East Coast boy and don't make it out there too often!
Another great video! I love that you said “pull” the needle toward you on the back course. That simple word made it so much easier to grasp the concept! Thanks for all that you have been doing with these videos!
Yes, on BC approaches I always thought of the needle as the airplane and the donut as the course/localizer = fly the needle to the course/donut. An HSI solves all the the confusion by setting the course arrow to the front course heading. One more detail is the BC localizer is more sensitive sense the antenna is several thousand feet closer - at the approach end rather than off the departure end of the approach runway.
"A good pilot is always learning" ✊🙏
Absolutely love your videos! I'm preparing for my instrument checkride and have found them to be invaluable. I recently just purchased the commercial course that you offer, and am loving it! So far I'm finding it to be far superior to Sportys or any other ground school I've tried. Thanks for helping me learn so well!
Thanks for this easy to understand explanation, I'm new to the channel but I'll be seeing all tje videos i missed, to catch up, you're doing a great work thanks for the efforts you putting in the contents , my appreciation.
Great I'm glad you found it easy as this is a somewhat challenging topic. Thanks for watching!
Great content! Best explanation of BC approaches Ive seen. thanks!
Thanks! Don’t get a chance to do these too often so a ground review is helpful
9:10 why do you not set that CDI to 178? Wouldn’t that give you normal sensing on the BC inbound?
your page is amazing. thank you for answering some of aviations more obscure concepts. I never recieved any teaching with regards to these topics in my training but I know i will need to use them someday soon. I feel a lot more confident now.
Thanks, so much, Hayden
At the 2:00 mark you show the To From flag switching as you pass the localizer antenna, that is incorrect, no To / From when tuned to localizer.
Loved the Britain analogy lol
The breakdown of the back course at the beginning made sense but that MAP with the dual localizers- yeah, I’m choosing a different approach or waiting for VFR conditions to fly there 😆
Thanks!
First good BC explanation I have seen. One little remark: it is not 437 feet DH AGL, but a MDA of 880 MSL (437 feet AGL), since it is a non precision approach. The BC button provides indeed normal sensing on the HSI when depressed on a BC approach. Thanks for sharing.
Yes thanks for that. It wasn't a decision height but an MDA. This is one of our clues that we're not getting vertical guidance on the approach like on an ILS
Cleared up so much for me, your videos have awesome visual explanation!
Amazing. Absolutely helpful. U will be a rich man 1 day
Awesome video. Helped cleared up a lot. Thank you!
Some of the newer OBS instruments have a BC light, which is a green light within the instrument. I’m not sure if that is a function that if you select back course it illuminates and puts the OBS 180° out of phase so that you would fly it like a normal localizer or it’s just a reminder light. On the G 1000 there is a BC button which I believe sets the unit up as a back course. Selecting this button, makes the CDI course selector flip 180° and line up with the opposite runway of the normal ILS. Reverse sensing which is a horrible term and it’s not true, is never experienced when you fly a HSI.
Just had to fly one of these trying to get home in the Simulator. Overcast at 600ft, runway height 300ft. ATC (vatsim) was super confused, and I had one missed approach. Eventually got it. Looking up how to do this properly now. If I'd lost navigational awareness, I would have had to either fly a tailwind approach, or divert to a different airport and drive home (in sim of course).
Awesome video!
Oy! You guys are driving on the wrong side of the street 😂 Great video, thank you.
Very well done!
Great Explaination. Thanks
Two questions here. Does the BC button allow you to fly outbound on a front course only localizer that is using an HSI. Remember the HSI will always point to the inbound course regardless, if you are flying to the localizer 180° from, the approach end or flying outbound opposite the inbound course using the HSI. The ILS 30L at St. Louis downtown has the aircraft on the miss intercepting the localizer and flying outbound back to the hold, which is also the initial approach fix for the inbound.
To avoid reverse sensing indications can you just fly a loc bc by putting in the opposite heading at the top of your obs vor instrument without the need of an hsi?
Thanks for this!
In Europe Back Course Approaches are forbidden due to the high number of fatalities
At 4:31 in the video, you refer to the minimums of the back course approach as "decision height". I disagree with using that term. What you highlight in the video is the minimum descent altitude (MDA), which is 880 feet as referenced on the barometric altimeter. A decision height (DH) is only applicable on a CAT II or CAT III ILS approach and is referenced by a radio altimeter. A decision altitude (DA) is applicable on a CAT I ILS and is referenced on the barometric altimeter. DA and DH differ from an MDA in that on a precision approach, upon reaching the decision point, DA or DH, you must meet the criteria for continuing the approach or execute a missed approach. On a non-precision approach, reaching the MDA is only the lowest altitude you may fly until you either reach the missed approach point or acquire the visual cues necessary to descend from the MDA to make a normal landing. Using the old "dive and drive" technique for a non-precision approach, you might reach the MDA way before the missed approach point. It is perfectly legal to fly along at MDA in this circumstance and wait until reaching the missed approach point, which could be referenced by either time or maybe a DME indication. By calling the MDA on the LOC BC a "decision height", you could introduce a misconception on the part of the student as to which this minimum is called and therefore cause confusion when other concepts are introduced in subsequent training.
I’m sure he misspoke and can tell the difference.
If the TO/FROM flag agrees with whether you're flying to/from, chase the needle. If the flag disagrees with how you're flying, then you correct backward. I explained that poorly, it it makes sense to me.
Makes sense to me, if flag says TO, you need to fly TO the deviation on the CDI(needle deflects right, you fly to the right).
If flag says FROM, you need to fly away from the deviation (needle goes right, you fly left)
I really dislike the Aspen backcourse because it deviates from the norm, even if the norm is somewhat obscure and conveluted
Accidentally called the MDA a DH at time 4:30
KHQZ uses the back course cause they don't have a ton of money. The tower doesn't have radar and the wonderful controllers just chill up there with binoculars! They're really friendly and funny guys!
The way I am understanding is…..if you want to learn Back Course approaches…..go to Great Britain!!!!!
But we don't have ILS / VOR in our cars... although we should, given the weather
My memory aid on a BC: “I *AM* the needle!”
Good one, Walter !
Reverse sensing doesn't exist. Turn it 180°, and it will be correct.
Because if you factor in which direction you are flying on the CDI, and see it like you're flying downwards, then the needle is right
Hopefully they get rid of back courses, that doesnt sound so safe with possibility of getting confused with the needles.
of course. I quit instrument training, cant understand it.
💯💯
Im sorry, but isnt it easier to say: this is what you enter into your Nav radios; this is the course to fly on approach (obviously the course opposite the RW with ILS); ignore the vertical guidance; at Mininum do A or B or C and you're good as gold?! I say so because I've watched a number of these backcourse videos and most are tangled in the technicalities rather than simplifying what needs to be done and when to do them. I'm as noob as they come in flying jargon but my interest in Sim flying (particularly MSFS) keeps me interested in these niceties but I need them broken down into digestible bits.
This isn't a takedown of your video please - I just need something more bare bones than I'm getting wherever I turn to on UA-cam.
This is why we just fly the RNAV
Easier just to say that you become the needle
MHz, not Hz.
Nope, he means Hz. The carrier is in the 100 and 300 Mhz range for the localizer/glideslope respectively. The tones are 90/150Hz modulated on the carrier.