Height/Altitude question.

[derekliston]

Somebody please explain this one to me. I fly from Warwick which has an elevation of 1536ft or thereabouts, therefore if I am flying 1000ft circuits I am at 2500ft. So why then do helicopters, army included make radio calls like "Departing Warwick tracking to Oakey, not above 500" Do they have different rules? because technically, at Warwick they would be 1,000ft below ground! I don't have a problem with it, I just want to understand why.

 

 

[Downunder]

I guess they mean "500 agl" . As you have pointed out it is obviously not msl, so must be agl.

 

 

[derekliston]

I guess they mean "500 agl" . As you have pointed out it is obviously not msl, so must be agl.

Yes, but why? If you are flying and someone on the radio asks your height don't you give it AMSL?

 

 

[Downunder]

Yes I do give msl.

 

Maybe it's simply a lazy way of saying "we will be flying low" and not putting in any effort to determine correct msl altitude.

 

I don't fly choppers.

 

 

[Nightmare]

As far as I know, all height reports need to be reported in AMSL, so there is no confusion. Are you sure they didn't actually say "500 above the ground" or similar?

 

 

[poteroo]

In my experience, choppers and aggies who are intending to fly cross-country at 500ft agl may give a departure call something like 'tracking 360, 500 agl' or, '500agl/tr 360'. That's not to say that they might drop a bit lower over uninhabited country, or pull up a little to overfly habitation if it can't be circum-navigated. happy days,

 

 

[derekliston]

As far as I know, all height reports need to be reported in AMSL, so there is no confusion. Are you sure they didn't actually say "500 above the ground" or similar?

Just those words 'Tracking to Oakey not above 500'

 

 

[Geoff13]

Just those words 'Tracking to Oakey not above 500'

Next time you hear them, ask what tunnel they are flying through.

 

 

[Happyflyer]

In my experience helicopters do have a different set of rules. I don't think they are written down and I think making them up on the spot must be taught as part of the course.

 

 

[Downunder]

In my experience helicopters do have a different set of rules. I don't think they are written down and I think making them up on the spot must be taught as part of the course.

You mean like flying in from any direction, at any height, straight to the fuel bowser........ I do think I know where you're coming from...

 

 

[frank marriott]

Without being picky, or debating the "correct" reporting levels , I have no problem with someone reporting tracking not above 500' as I take it as "low level" and (to me at least) it would mean AGL.

 

 

[Head in the clouds]

In my experience helicopters do have a different set of rules. I don't think they are written down and I think making them up on the spot must be taught as part of the course.

C'mon folks ... now you're making it up as YOU go along. Yes, we do have different rules for helicopters and you ought to be embarrassed that you don't know this. We ALL fly according to the same rulebook - please know your Regs folks or you weaken our amateur flyers' position.

 

Hint - rotary straight in approach 'can be' 700agl, or below, whereas fixed wing circuit is 1000agl and rotary visual minima - speed reduced - is also way less than fixed wing - just 20% ... because in event of whiteout a helo can hover and land, a plane cannot.

 

These different rules are due to the relative mission capabilities of the two very different aircraft types, as you might expect.

 

Generally rotary doesn't have to conform to any circuit pattern, and yes, can approach directly below other aircraft direct to their hangar, the bowers, etc. And can depart in manners that may confuse fixed wing flyers who haven't availed themselves of all the air navigation rules that perhaps they ought to have ...

 

The main thing that might appease the now offended - is that when rotary flyers take benefit of their 'special rules' is that, generally, they should only do so when they don't cause conflict to other traffic.

 

Unfortunately for some fixed wing flyers' sensibilities is that helos are so manoeuvrable that those flyers regularly think that conflict might exist when in fact it's far from being so.

 

 

[derekliston]

C'mon folks ... now you're making it up as YOU go along. Yes, we do have different rules for helicopters and you ought to be embarrassed that you don't know this. We ALL fly according to the same rulebook - please know your Regs folks or you weaken our amateur flyers' position.Hint - rotary straight in approach 'can be' 700agl, or below, whereas fixed wing circuit is 1000agl and rotary visual minima - speed reduced - is also way less than fixed wing - just 20% ... because in event of whiteout a helo can hover and land, a plane cannot.

 

These different rules are due to the relative mission capabilities of the two very different aircraft types, as you might expect.

 

Generally rotary doesn't have to conform to any circuit pattern, and yes, can approach directly below other aircraft direct to their hangar, the bowers, etc. And can depart in manners that may confuse fixed wing flyers who haven't availed themselves of all the air navigation rules that perhaps they ought to have ...

 

The main thing that might appease the now offended - is that when rotary flyers take benefit of their 'special rules' is that, generally, they should only do so when they don't cause conflict to other traffic.

 

Unfortunately for some fixed wing flyers' sensibilities is that helos are so manoeuvrable that those flyers regularly think that conflict might exist when in fact it's far from being so.

Interesting how easy it is to open a can of worms on this forum. I don't and didn't have a problem with any of it. It was quite clear that 'not above 500' was AGL. I was merely curious about the reasoning and I confess that as a fixed wing pilot I am really not familiar with rules applying to helicopters. Since we should all apparently know the rules I might point out that circuit height for fixed wing can be 500, 1000 or 1500 AGL depending on speed and I know of one airstrip with a circuit height of 700 ft AGL.

 

 

[frank marriott]

I know of one airstrip with a circuit height of 700 ft AGL.

That would be interesting! Or do you mean 700' elevation?

 

 

[derekliston]

That would be interesting! Or do you mean 700' elevation?

Coominya Qld is under the Amberley 1500ft airspace so circuit height is 700ft AGL which is 1000ftAMSL unless any Coominya flyers can tell me otherwise!

 

 

[frank marriott]

Coominya Qld is under the Amberley 1500ft airspace so circuit height is 700ft AGL which is 1000ftAMSL unless any Coominya flyers can tell me otherwise!

Now I get what you are saying - As listed in the ERSA for that particular airport.

 

 

[Jaba-who]

There's more to it than all of this.

 

Ag ops operate under a different set of rules ( I forget the number but it's something like Part 135 or something like it Agricultural Operations - number given to me by an ag operator when I raised the issue with him. ) as best I remember They are allowed to use AGL as long as they don't climb above 500ft AGL when they have to revert to AMSL. Some other rule changes include self selection of runway against the flow other traffic and a few other crazy things. )

 

There is no option for helicopters to operate under part XYZ Ag Ops unless they are doing ag Ops but when I was flying Helos we did it all the time and especially out over water flying coastal,or in and out from the reef ( using the same principle that as soon as you climb up you revert to AMSL.

 

I have no issue with any of that except at YATN we have a number of RAAus guys who have begun mimicking the ag guys and using AGL but for ridiculous heights like "microlight XYZ 10 miles south at 3500 AGL" or even greater heights. Airfield is at 2500 AMSL so when they use this it becomes very confusing especially if they have crackly Comms and you miss the "AGL" part. It's been raised and the regs looked at. But surprisingly there actually is no regulation that says in black and white that "calls must be made in AMSL".

 

There is circuitous statements that say altimeters must be calibrated and set to reflect altitude as AMSL and that you must make certain radio call stating your altitude. The average joe would interpret that to infer that the word altitude means what's on the dial as AMSL and you should call what you read on the dial but but nowhere that actually says you have to state the altitude as you read it from the altimeter. We looked at it to try and make these guys call in AMSL but we couldn't find anything. CASA said they interpret it that way but these guys just say "F__k them. It doesn't say that at all and we'll do what we want to do because what we want to do is within what the rules say ". A legal guy ( non aviation) said even though they are stupid they are legally correct.

 

These guys here doing their own calculations and their estimates of the ground level, and where they are ( which could be anything as it's hills, valleys, flats and peaks everywhere) and give calls as AGL which can have no bearing on their altitude AGL in a few seconds time.

 

Very problematic.

 

 

[derekliston]

There's more to it than all of this.Ag ops operate under a different set of rules ( I forget the number but it's something like Part 135 or something like it Agricultural Operations - number given to me by an ag operator when I raised the issue with him. ) as best I remember They are allowed to use AGL as long as they don't climb above 500ft AGL when they have to revert to AMSL. Some other rule changes include self selection of runway against the flow other traffic and a few other crazy things. )

There is no option for helicopters to operate under part XYZ Ag Ops unless they are doing ag Ops but when I was flying Helos we did it all the time and especially out over water flying coastal,or in and out from the reef ( using the same principle that as soon as you climb up you revert to AMSL.

 

I have no issue with any of that except at YATN we have a number of RAAus guys who have begun mimicking the ag guys and using AGL but for ridiculous heights like "microlight XYZ 10 miles south at 3500 AGL" or even greater heights. Airfield is at 2500 AMSL so when they use this it becomes very confusing especially if they have crackly Comms and you miss the "AGL" part. It's been raised and the regs looked at. But surprisingly there actually is no regulation that says in black and white that "calls must be made in AMSL".

 

There is circuitous statements that say altimeters must be calibrated and set to reflect altitude as AMSL and that you must make certain radio call stating your altitude. The average joe would interpret that to infer that the word altitude means what's on the dial as AMSL and you should call what you read on the dial but but nowhere that actually says you have to state the altitude as you read it from the altimeter. We looked at it to try and make these guys call in AMSL but we couldn't find anything. CASA said they interpret it that way but these guys just say "F__k them. It doesn't say that at all and we'll do what we want to do because what we want to do is within what the rules say ". A legal guy ( non aviation) said even though they are stupid they are legally correct.

 

These guys here doing their own calculations and their estimates of the ground level, and where they are ( which could be anything as it's hills, valleys, flats and peaks everywhere) and give calls as AGL which can have no bearing on their altitude AGL in a few seconds time.

 

Very problematic.

Don't know if they still do, but back in the last century (truly!!!) when I learned to fly in the UK they used two different altimeter settings. QFE if you were flying circuits or until you departed the airfield at which time you changed over to area QNH and then back to QFE on return to circuit. QFE was in fact field elevation which meant that ground level read zero on the altimeter. Took me a while to adjust to landing at, for example 1500ft here in Warwick! Just an addition to the dialogue, not for any other reason but aviation trivia.

 

 

[facthunter]

I think South Africa uses QFE. Whatever you use everyone should be the same or the vertical separation you think you have may not exist. Nev

 

 

[Jaba-who]

Don't know if they still do, but back in the last century (truly!!!) when I learned to fly in the UK they used two different altimeter settings. QFE if you were flying circuits or until you departed the airfield at which time you changed over to area QNH and then back to QFE on return to circuit. QFE was in fact field elevation which meant that ground level read zero on the altimeter. Took me a while to adjust to landing at, for example 1500ft here in Warwick! Just an addition to the dialogue, not for any other reason but aviation trivia.

Yep. I've used it a couple of times "unofficially" when doing some circuit work for the interest etc but as far as I am aware we aren't "allowed" to use it in Oz.

 

 

[Yenn]

This thread just points up the stupidity of some pilots. To use AGL is ridiculous unless you have an altimeter that can measure AGL. In places that I fly my AGL call would be incorrect, before I had been able to give it. The only way to get an accurate AGL is with radio altimetry and I have never seen an RAAus plane with that fitted.

 

 

[facthunter]

Stick with the rules. You don't drive on the wrong side of the road when you go to some other country. nev

 

 

[kaz3g]

Don't know if they still do, but back in the last century (truly!!!) when I learned to fly in the UK they used two different altimeter settings. QFE if you were flying circuits or until you departed the airfield at which time you changed over to area QNH and then back to QFE on return to circuit. QFE was in fact field elevation which meant that ground level read zero on the altimeter. Took me a while to adjust to landing at, for example 1500ft here in Warwick! Just an addition to the dialogue, not for any other reason but aviation trivia.

We routinely used QFE when training glider pilots a few decades ago.

 

Kaz

 

 

[Nightmare]

Coominya Qld is under the Amberley 1500ft airspace so circuit height is 700ft AGL which is 1000ftAMSL unless any Coominya flyers can tell me otherwise!

You are spot on, the elevation at YBCM is 300ft so the altimeter reads 1000ft AMSL at circuit height. I have my aircraft hangered there.

[Neil_S]

There's more to it than all of this.Ag ops operate under a different set of rules ( I forget the number but it's something like Part 135 or something like it Agricultural Operations - number given to me by an ag operator when I raised the issue with him. ) as best I remember They are allowed to use AGL as long as they don't climb above 500ft AGL when they have to revert to AMSL. Some other rule changes include self selection of runway against the flow other traffic and a few other crazy things. )

There is no option for helicopters to operate under part XYZ Ag Ops unless they are doing ag Ops but when I was flying Helos we did it all the time and especially out over water flying coastal,or in and out from the reef ( using the same principle that as soon as you climb up you revert to AMSL.

 

I have no issue with any of that except at YATN we have a number of RAAus guys who have begun mimicking the ag guys and using AGL but for ridiculous heights like "microlight XYZ 10 miles south at 3500 AGL" or even greater heights. Airfield is at 2500 AMSL so when they use this it becomes very confusing especially if they have crackly Comms and you miss the "AGL" part. It's been raised and the regs looked at. But surprisingly there actually is no regulation that says in black and white that "calls must be made in AMSL".

 

There is circuitous statements that say altimeters must be calibrated and set to reflect altitude as AMSL and that you must make certain radio call stating your altitude. The average joe would interpret that to infer that the word altitude means what's on the dial as AMSL and you should call what you read on the dial but but nowhere that actually says you have to state the altitude as you read it from the altimeter. We looked at it to try and make these guys call in AMSL but we couldn't find anything. CASA said they interpret it that way but these guys just say "F__k them. It doesn't say that at all and we'll do what we want to do because what we want to do is within what the rules say ". A legal guy ( non aviation) said even though they are stupid they are legally correct.

 

These guys here doing their own calculations and their estimates of the ground level, and where they are ( which could be anything as it's hills, valleys, flats and peaks everywhere) and give calls as AGL which can have no bearing on their altitude AGL in a few seconds time.

 

Very problematic.

It was my understanding that :-

 

Altitude is always height above mean sea level ie AMSL

 

Elevation is the height of terrain above sea level e.g an airfield's elevation or mountain's elevation

 

Height is the difference between altitude and elevation i.e. AGL

 

So given these definitions if the manual says you should state your altitude then it means AMSL, and if you are cruising above hilly terrain how the hell can you give an accurate height AGL? It varies every second.

 

Cheers,

 

Neil