Is it just me....

You've gone too far! Yes there is, according the Instrument Flying Handbook:
"VOR Operational Errors
Typical pilot-induced errors include:
1. Careless tuning and identification of station.
2. Failure to check receiver for accuracy/sensitivity.
3. Turning in the wrong direction during an orientation.
This error is common until visualizing position rather
than heading.
4. Failure to check the ambiguity (TO/FROM) indicator,
particularly during course reversals, resulting in reverse
sensing
and corrections in the wrong direction."​
dtuuri
I don't care what that says -- there really is no such thing as "reverse sensing." The equipment still senses and indicates exactly the same all the time.
 
But I do like your way of looking at the CDI: it's elegant and situational. It's just not the way I think when I'm in the plane.
I understand that a lot of people don't think this way, but I also see a lot of people trying to go the wrong way when they don't. If you have another system that works for you, great. But if you're going to teach VOR orientation, interception, and tracking, I strongly teaching it this way.

There is more than one way to think about it that will always give the right answer. I do believe that your way is the best way I've seen to TEACH it. But that doesn't mean that other people are confused when they talk about it in ways that make you bang your head.
Well, I've seen too many people who've learned with all that left/right stuff be unable to do it when we started instrument training, and had to relearn it the way I've explained it in order to get it right. That's why I get frustrated when someone pops up here and says "Hey, it's simple -- if the needle is left, you turn left," as anyone who accepts that is headed down a difficult path later on when I have to work against the Laws of Primacy and Exercise during instrument training.
 
You can set the OBS to a northerly course, but not to a northerly heading. Mixing up the terms course, track, and heading is the path to confusing the problem. Here's a reminder:

  • Course is the direction over the ground you want to fly.
  • Heading is the direction the nose is pointed.
  • Track is the direction over the ground you are actually flying.
There is no such thing as "reverse sensing". When a VOR is selected, the needle will always go to the side of the indicator corresponding to the cardinal direction of the selected course line from the aircraft's position. "Reverse sensing" is a misconception associated with thinking left/right instead of east/west or north/south and does not exist.

So let's take the scenario discussed above -- heading 010, 180 course selected, currently on the 185 radial. For orientation, with a 180 course selected, the top of the CDI corresponds to south, the bottom to north, the left side to east, and the right side to west. In this situation, you are located west of the 180/360 course line, meaning the course line is east of you. Therefore, the needle will be deflected to the east side of the CDI, which happens to be the left side. If you look at that side of the case, you'll see a big E or 9, meaning you have to fly east or 090 to go straight-line/shortest distance to that course line.

In addition, you'll see a FROM flag, indicating you are south of the perpendicular line across the course line through the station. You can then see that to join that course line headed south (outbound), you have to turn southeast. Now you look at your heading indicator (HI). With 010 at the top, you see that a southeasterly heading like 135 is to the right of the nose, so you turn right to join that course line southbound even though the needle is deflected to the left.

Now, let's say you want to join that same 180/360 course line headed north instead of south, but for whatever reason (say you're training for LOC BC approaches), you leave the OBS set to 180. Everything in the second paragraph above is still true -- the needle is still deflected to the east (left) side of the CDI. However, if you are east of that course line and south of the perpendicular, you can easily visualize that you need a northeast heading to join that course line northbound -- and you can help yourself by looking at the CDI to do that. Since the needle is deflected east, and you want to go north, pick a heading off that CDI OBS ring between the side to which the needle is pointing (E/9) and the desired course (N/36) on that OBS, such as 045. Now look at the heading indicator, and you'll see that once again a right turn is needed to get to the desired heading despite the needle being to the left.

The key is using the CDI to tell you the direction you want to fly to get to the desired course line, and then using the HI to tell you which way to turn.

Let's say you want to join the 180 radial inbound from south of the station, i.e., a 360 course TO the station. You set the OBS to 360, see that it is deflected 5 degrees to the east side of the case (in this case, the right side). That means you are 5 degrees west of the 180 radial, or on the 185 radial. Your heading indicator is on 010. Do you need to turn left, right, or not at all to intercept the 180 inbound?

The answer is "insufficient information". The initial answer might be that since we are west of the course line, but our heading is to the east of it, we can just stay on heading and intercept. That would be true if and only if you see the needle moving from right to left showing your track is angled towards the selected course line.

However, say you have a strong wind from the east such that your course is 355 even though your heading is 010. In that case, you'll see that not only is the needle 5 degrees to the east of 360, it's moving further east, meaning you are moving further away from the course line. You will have to turn further east to counter the wind, and that means looking at the HI to see you need to turn right of 010. As you turn, the needle will stop moving as you exactly counter the wind, and then start to move back the other way towards the west side of the CDI once your track is moving towards the 180 radial.

OTOH, let's say the needle is stationary, showing you are tracking directly to the station, but on the 185 radial, not the 180 radial. In that case, you'll have to make a small heading change to the east to get your track more easterly towards the desired course line. Of course, if you're flying a holding pattern at a VOR station, you probably don't want to make much of an adjustment at all, maybe none. Inside one minute from the station, being 5 degrees off the radial is very well within the protected airspace. If you do nothing and the needle stays where it is, you'll fly right over the station only 5 degrees off the desired course, but if you start trying to catch it inside 2 miles, you're more likely to get yourself in an S-turning chase than to cross the station wings-level on or close to the desired inbound course.

Now, let's go back to that upside-down case, where you want to track backwards, like going out the front course or in the back course of a LOC. Remember that the LOC signal is different from VOR, and it doesn't matter what you spin on the OBS, it will act like you have set the forward direction (the front course inbound course or back course outbound course). If you set the CDI on the forwards direction, then you can use the technique I described above to track it. Let's say we're trying to go inbound on the front course of a LOC 27. You put the 27 at the top. Say you are south of the course -- the needle deflects to the right (north) side of the CDI. If you fly a heading to the north side of 270 (e.g., 300), that will take you to the localizer in the direction you want to go (wind factors ignored for the moment).

What about going backwards on that 27 localizer, i.e., out the inbound or in the outbound? If you set the desired course (090) on the CDI, that will have no effect on needle movement. If you are south of the localizer, the needle will still deflect to the right side of the case even though you have now caused the S/18 to be on that side. Now you have to ignore the numbers on the OBS ring, and think to yourself "with a 27 localizer, the right side is north, so I need a heading north of the 090 course such as 060 to intercept." And if you are on 090 at this point, that is a left turn, not right, even though the needle is deflected right. That's what people mistakenly call "reverse sensing" even though it is still responding the same based on the position of the aircraft.

You can help yourself in this case by putting the OBS on 27 instead of 9, which will give you 27 at the top and 9 at the bottom. Now the needle is deflected towards the S/18, and if you look between the 18 and the desired 9 course at the bottom of the CDI, you will see that a northeasterly heading such as 060 is needed to get you onto the localizer. If you're currently headed 090, your heading indicator tells you that you need a left turn to alter your track so it will intercept the localizer.

IOW, to fly a localizer , you set the OBS to the forwards direction regardless of which way you want to fly it, see what the needle points to, pick a heading between the desired course (i.e., top for forwards, bottom for backwards) and the direction to which the needle points, and then look at the HI to decide which way to turn.

Whew! My fingers are tired.

Yup.
.....my head hurts. I'd hate to see your explanation of ADF navigation :confused:
 
I don't care what that says -- there really is no such thing as "reverse sensing." The equipment still senses and indicates exactly the same all the time.

Strangely enough, I'm going to agree with Ron here.

The term really should be "reverse indicating" and I actually believe I've seen this term used for CDIs.

Well, actually, that's technically wrong as well because it's still indicating the same as normal, it's just opposite for the course the plane is on. Maybe we should make "back-course-ing" a verb?
 
Minor nit: if you're south of a LOC 27 course, the needle will be deflected to the right, as you said in the previous paragraph. If you put the OBS on 27 then the needle is seen to be deflected towards the N/36, and you can find 060 between 360 and the desired 090 course.
I thought that's what I said. The problem is when you twist the OBS to the backwards course you're trying to fly (090), in which case the needle still deflects right, but now S/18 is there instead of N/36, and that will send you in the wrong direction if you follow it.
 
I don't care what that says -- there really is no such thing as "reverse sensing." The equipment still senses and indicates exactly the same all the time.

If, when it senses normally it requires normal thinking, then when it requires reverse thinking it must be reverse sensing, no?

dtuuri
 
Strangely enough, I'm going to agree with Ron here.

The term really should be "reverse indicating" and I actually believe I've seen this term used for CDIs.

Well, actually, that's technically wrong as well because it's still indicating the same as normal, it's just opposite for the course the plane is on. Maybe we should make "back-course-ing" a verb?
maybe the term "bass-ackwards" would be acceptable? Main thing to keep in mind; if the big "S" is up on the OBS and the big "N" is up on the DG the CDI will be indicating bass-ackwards.
 
If, when it senses normally it requires normal thinking, then when it requires reverse thinking it must be reverse sensing, no?

dtuuri

What Ron's is trying to say is that it still shows lateral displacement from the selected course same as always, it's just now you've selected a course that's 180 degrees from your intended course. Here's where Ron's point makes sense; if you think of this as a left/right indicator this will be confusing, if you think of it like a course deviation indicator then it will work fine in your head (but will still be backwards from what you're used to seeing, so still confusing). So, yes, it's reverse thinking but not reverse sensing.

Do I get a gold star Ron?
 
Well, that depends on whether the "sensing" is in the indicator or in your mind :dunno:

I suppose, but I'm not sensing what an instrument displays personally, I read it and interpret it. The only sensing going on is the CDI sensing the radio signals from the VOR. But, yes, I agree that it's all semantics which really are just an means to a end.
 
So, yes, it's reverse thinking but not reverse sensing.

The folks who wrote the IFH defined the term in their glossary, so we shouldn't criticize students who study the book and use the term in that way too:
"Reverse sensing. The VOR needle appearing to indicate the
reverse of normal operation.'​

We should just make the point in your post I quoted.

Dtuuri
 
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I understand that a lot of people don't think this way, but I also see a lot of people trying to go the wrong way when they don't.
Are these people who try to go the wrong way instrument rated pilots, or beginning instrument students whose only exposure to VORs was during primary training?
If you have another system that works for you, great. But if you're going to teach VOR orientation, interception, and tracking, I strongly teaching it this way.
It's not really "another system". In the example I gave to TMP above, I would say the needle is deflected to the left, showing that if you were facing in the 180 direction (OBS selection), the desired course would be to your left. That's completely equivalent to saying that the needle is deflected to the east side of the CDI, showing that the desired course is somewhere to the east of your location. I agree though, that if you're going to teach it, you should try to explain it in the way that is least likely to lead to confusion.

I'd be curious to know how you teach students how to tell when they're still approaching a fix defined by a crossing radial, and when they've passed it. I was taught a trick that seems to be a little easier to justify and understand using my way of thinking than with yours.
I thought that's what I said. The problem is when you twist the OBS to the backwards course you're trying to fly (090), in which case the needle still deflects right, but now S/18 is there instead of N/36, and that will send you in the wrong direction if you follow it.
Maybe I misread what you wrote, but I thought you said that with the OBS on 270, the needle is deflected to S/18, and you find the intercept heading between 9 and 18. That would be true if you were north of course, but then you picked 060. Doesn't really matter, I know what you meant.
 
The irrelevancy with questions like this.....if I turn the knob the wrong way and discover it's the wrong way, I can always turn it back the right way.

I know I'm late to the party for a me-too but I found these questions highly annoying and impractical. No examiner or check pilot has ever batted an eye or chuffed at a momentary turn of a obs for example in the wrong direction.
 
Most instrument airplanes I've been in have not just one, but two RMIs driven by two remote compasses. Maybe you won't personally ever see one...

Nice attempt to deflect. The question doesn't test the concept. A test of the concept would ask about the concept of remote compasses, not the mechanics of using a particular model of remote compass.

Now tell me how many instrument trainers have an RMI and/or a remote compass. Now tell me how many folks will remember some trivial tidbit when they do finally encounter a remote compass. Be sure to support your response with facts, not just supposition and hearsay.

In short, you just don't get it do you?
 
The folks who wrote the IFH defined the term in their glossary, so we shouldn't criticize students who study the book and use the term in that way too:
"Reverse sensing. The VOR needle appearing to indicate the
reverse of normal operation.'​
We should just make the point in your post I quoted.

Dtuuri
I've never seen a properly functioning VOR needle appear to indicate the reverse of normal operation -- NEVER.
 
Are these people who try to go the wrong way instrument rated pilots, or beginning instrument students whose only exposure to VORs was during primary training?
The latter. You can't get through your IR very well thinking that way.

I'd be curious to know how you teach students how to tell when they're still approaching a fix defined by a crossing radial, and when they've passed it. I was taught a trick that seems to be a little easier to justify and understand using my way of thinking than with yours.
I teach cardinal directions, just like I said. Makes more sense when they're looking at their chart.
 
Nice attempt to deflect. The question doesn't test the concept. A test of the concept would ask about the concept of remote compasses, not the mechanics of using a particular model of remote compass.

Now tell me how many instrument trainers have an RMI and/or a remote compass. Now tell me how many folks will remember some trivial tidbit when they do finally encounter a remote compass. Be sure to support your response with facts, not just supposition and hearsay.

In short, you just don't get it do you?

I'm quite comfortable with what I've already stated, namely that the question can be asked and answered without using a figure of any specific model. They all work the same and you can reason it out if you happen to know the underlying concept.

You guys are missing the point that it's just another question on radio IFR navigation and you shouldn't be obsessed with getting every friggin' one right. The FAA just wants to see that you've remembered what you've studied broadly enough, not perfectly.

We all want to score highly, of course, and I was no different. Just don't obsess over it by confusing memorizing isolated factoids with the big picture. You're better off knowing where to find the answers you don't remember than in trying to remember all of them in the first place.

dtuuri
 
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I've never seen a properly functioning VOR needle appear to indicate the reverse of normal operation -- NEVER.

Would it be correct to say that you believe the FAA has chosen a misleading term/definition for the concept they're trying to describe? If so, what would be a better term/definition? Reverse perception?
 
Would it be correct to say that you believe the FAA has chosen a misleading term/definition for the concept they're trying to describe?
Absolutely yes.
If so, what would be a better term/definition? Reverse perception?
I don't think any special term/definition is necessary, just better education on how it works and how to use it properly.
 
The latter. You can't get through your IR very well thinking that way.
It's not surprising then, because I imagine that most CFIs aren't concerned with teaching the details of VOR navigation during primary training (trying to do that might even overwhelm a primary student -- how much detail do you give them?). So they give them a simplified heuristic and if the student isn't interested enough to figure out how it REALLY works, they come away with a muddled, and mostly wrong, understanding.

I teach cardinal directions, just like I said. Makes more sense when they're looking at their chart.
Care to share any details, or is that a "trade secret"? FTR the trick I was taught is that if you dial in the radial, the needle deflects toward the station if you're approaching the fix, and away if you've passed it. You just need the situational awareness to know on which side the station is on.
 
You guys are missing the point that it's just another question on radio IFR navigation and you shouldn't be obsessed with getting every friggin' one right. The FAA just wants to see that you've remembered what you've studied broadly enough, not perfectly.

What you've said is that the FAA takes the position that it is more important for people to miss a question than it is to ask questions which are relevant. Why do you claim to speak for the FAA? Why do you support their poorly stated and ill directed written tests? Change only happens when folks finally recognize that what is being done is wrong.
 
Care to share any details, or is that a "trade secret"? FTR the trick I was taught is that if you dial in the radial, the needle deflects toward the station if you're approaching the fix, and away if you've passed it. You just need the situational awareness to know on which side the station is on.

As Ron said "just like I said", I assume he means not thinking in terms of left or right in relation to the aircraft but thinking in terms of cardinal direction in terms of the selected VOR course.

At the very least what makes sense to me is to always have the "big picture" in your head of mentally where you are in relation to the VOR, where the selected course is on the CDI/HSI, and compare that to where the instrument is indicating.

Thus, East of the course and West of the course will always be true no matter if you flip the OBS course 180 degrees but if you think in terms of left/right it will become backwards. Obviously you can still say left or right of course but without the big picture these aren't as useful.

Essentially what I took away from Ron is that no matter what you must understand where you are in relation to the course selected. This can be left or right of the course or N/S/E/W of the course. Left/right can change depending on the selected course (0 deg or 180 for example) but East/West do not.

Good trick for the fix crossing. I like that.
 
Care to share any details, or is that a "trade secret"? FTR the trick I was taught is that if you dial in the radial, the needle deflects toward the station if you're approaching the fix, and away if you've passed it. You just need the situational awareness to know on which side the station is on.
Right -- you need that situational awareness, and that isn't always obvious. My method is to dial in the cross-radial and see which side of the case the needle is on, then see what cardinal direction that puts the radial from you. Say you're northbound on an airway, and the cross-radial is the ABC240. Put 240 on the top, and that will put 330 (a northwesterly direction) on the right side and 150 (a southeasterly direction) on the left side. If the needle points left, the cross-radial is southeast of you, i.e., behind you if you're headed north. If the needle points right, the cross-radial is northwest of you, so it's still out front of you if you're headed north. Another method I find works is to imagine yourself in the middle of the CDI, then point from center to your current course and see if you're pointing to the needle or away from it.
 
As Ron said "just like I said", I assume he means not thinking in terms of left or right in relation to the aircraft but thinking in terms of cardinal direction in terms of the selected VOR course.

At the very least what makes sense to me is to always have the "big picture" in your head of mentally where you are in relation to the VOR, where the selected course is on the CDI/HSI, and compare that to where the instrument is indicating.

Thus, East of the course and West of the course will always be true no matter if you flip the OBS course 180 degrees but if you think in terms of left/right it will become backwards. Obviously you can still say left or right of course but without the big picture these aren't as useful.

Essentially what I took away from Ron is that no matter what you must understand where you are in relation to the course selected. This can be left or right of the course or N/S/E/W of the course. Left/right can change depending on the selected course (0 deg or 180 for example) but East/West do not.

Good trick for the fix crossing. I like that.
By George, I think he's got it!
:applause:
 
Change only happens when folks finally recognize that what is being done is wrong.

Why don't you make it your mission to tell them they shouldn't ask questions about the material they've included in the book you apparently didn't take the time to read? Now buzz off.

dtuuri
 
Most instrument airplanes I've been in have not just one, but two RMIs driven by two remote compasses. Maybe you won't personally ever see one...

dtuuri

That's nice for you. None of the instrument airplanes I've flow have such toys. Needless to say, other than the IR written, I've never seen one.
 
Good trick for the fix crossing. I like that.
I like it too, but now I actually like Ron's second method better.
Another method I find works is to imagine yourself in the middle of the CDI, then point from center to your current course and see if you're pointing to the needle or away from it.
Thanks. This is really good -- just as intuitive as the way I was taught, and easy to understand in terms of cardinal directions. Also doesn't require that you know ahead of time where the station is. I think you've made another convert today Ron. :)
 
That's nice for you. None of the instrument airplanes I've flow have such toys. Needless to say, other than the IR written, I've never seen one.

The answer's in the Instrument Flying Handbook in the chapter on flight instruments. That makes it fair game where I come from. It's not a memory test. You're not a bum if you don't get a 100%. Nobody takes you behind the hangar and shoots you for missing a few questions. Lighten up, study the real books not the answer books, pass the test and learn from your mistakes.

dtuuri
 
By George, I think he's got it!
:applause:

Yes, I get it. I will humbly admit that I did learn about something that I was doing which wasn't needed (mentally turning N/S/E/W into L/R of course) and could cause confusion or headaches. Overall I imagine this wont change how well I use a CDI but I do agree it is simpler and, in the crossing radial example, makes a lot of sense.

My "problem" was that I was just trying to make a simple point entirely off topic from CDI interpretation that you pounced on and made some fairly inaccurate statements about my intent and character and confused me into thinking you thought that I was using the CDI as a "turn L or R" indicator. It made it quite hard to learn anything afterwards. But, now that you're not accusing me of trying to propose how to use a CDI, George and me do indeed "get it".

I like you Ron, I bet you and I would butt heads some if I were your student, but as long as we didn't **** each other off too much I'd learn a ton.

P.S. I'm still annoyed at you but that's fine. :p
 
"What is the third fundamental skill in attitude instrument flying?"

Really? Do I need to know the order of these skills?
 
Why don't you make it your mission to tell them they shouldn't ask questions about the material they've included in the book you apparently didn't take the time to read? Now buzz off.

Buzz off? That's pretty rude. Maybe you can do better if I give you a second chance? Try real hard to be respectful...
 
Buzz off? That's pretty rude. Maybe you can do better if I give you a second chance? Try real hard to be respectful...
Haven't you figured out yet I'm not taking your bait? Beat it.

dtuuri
 
I submit the note at the bottom of your slide 23 is conclusive evidence of my point.

There are obsolete questions in commercially-prepared test aids and always have been. Whether or not you could actually get a question based on outdated versions of the IFH I can't say for sure, but I doubt it. The FAA test guides may lag behind and cause confusion, too, so that's why I included it in the tutorial--just in case.

Your kind words about my site motivated me to convert all the tutorials to iPad compatible ones over the past few days. It was a very tedious process, but wow, I see why everybody has 'em now ('cept me, I had to borrow for testing). I also added a "donate" button, thanks to you. :) These tutorials are extremely time-consuming, not to mention the hosting and software costs to publish.

dtuuri
 
[blink][blink] are you for real?

...
So I still ask the question - are you for real - and you haven't addressed why I asked the question. I'm sure I'm not the only one who asked that particular question.

Nice attempt to deflect. The question doesn't test the concept. A test of the concept would ask about the concept of remote compasses, not the mechanics of using a particular model of remote compass.

Now tell me how many instrument trainers have an RMI and/or a remote compass. Now tell me how many folks will remember some trivial tidbit when they do finally encounter a remote compass. Be sure to support your response with facts, not just supposition and hearsay.

In short, you just don't get it do you?

Why don't you make it your mission to tell them they shouldn't ask questions about the material they've included in the book you apparently didn't take the time to read? Now buzz off.

dtuuri

Buzz off? That's pretty rude. Maybe you can do better if I give you a second chance? Try real hard to be respectful...

Haven't you figured out yet I'm not taking your bait? Beat it.

dtuuri
On the chance somebody may have missed why I lost my patience with you, I'm posting this review. It isn't my nature to be rude, but it is my nature to defend myself. I don't mind a little give and take as long as I think I'm sparring in good humor with my antagonist, but some of your comments don't leave me with that feeling. I tried to ignore them and just respond to the reasonable ones you made, but I reached my limit. Sorry if I might have offended anyone else.

But I don't believe in using the ignore feature and I try not to hold a grudge, so I'm resetting my opinion of you to zero, uh, er, neutral :) and hope we can get along better from now on.

dtuuri
 
Yes, I get it. I will humbly admit that I did learn about something that I was doing which wasn't needed (mentally turning N/S/E/W into L/R of course) and could cause confusion or headaches. Overall I imagine this wont change how well I use a CDI but I do agree it is simpler and, in the crossing radial example, makes a lot of sense.

My "problem" was that I was just trying to make a simple point entirely off topic from CDI interpretation that you pounced on and made some fairly inaccurate statements about my intent and character and confused me into thinking you thought that I was using the CDI as a "turn L or R" indicator. It made it quite hard to learn anything afterwards. But, now that you're not accusing me of trying to propose how to use a CDI, George and me do indeed "get it".

I like you Ron, I bet you and I would butt heads some if I were your student, but as long as we didn't **** each other off too much I'd learn a ton.

P.S. I'm still annoyed at you but that's fine. :p
I didnt get the impression Ron was accusing YOU, but perhaps you were the example of the moment for all to benefit from.

No shame in exposing a lack of knowledge when you present yourself at the well for a drink.

Thanks to the both of you (and Azure in no small part) we all benefitted. Its all good.
 
Here is my latest irritant: the questions on the primary and supporting instruments. These questions are stupid for multiple reasons. The one reason I will gripe about is the verb "establishing" used by the FAA in their questions. When using this word, are they asking about transitioning from one flight mode to another, or while in a specific flight mode. For example: "Which instruments are considered primary and supporting for bank, respectively, when establishing a level standard rate turn?" I know they want you to know that AI is primary when you first want to go bank from level flight to initiate the turn, and that the turn coordinator is primary when you are making your standard rate turn. But "establishing" is such a sloppy word it's not evident which one they want. To answer my own question, "establishing" is apparently used by them in this question in contrast to the word "established", meaning they want you to answer as if you are "transitioning" to the turn from straight and level flight.

However, in the question: "What is the primary pitch instrument when establishing a constant altitude standard-rate turn," the word "establishing" doesn't seem to mean that you are "transitioning" to level flight. The correct answer assumes instead that you are already established in level flight.
 
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