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Emergency landing

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Emergency landing

Old 27th Jan 2016, 10:50
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Sid,
Interestingly, in your posted copy of the RFM for the H500 Height Velocity Diagram, it doesn't state "HEIGHT", it states on the vertical axis "ALTITUDE ABOVE TERRAIN - FEET"
So what's the difference between this and HEIGHT?
This is a HEIGHT VELOCITY DIAGRAM, not an ALTITUDE VELOCITY DIAGRAM. right?
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Old 27th Jan 2016, 12:56
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Sid,
Interestingly, in your posted copy of the RFM for the H500 Height Velocity Diagram, it doesn't state "HEIGHT", it states on the vertical axis "ALTITUDE ABOVE TERRAIN - FEET"
So what's the difference between this and HEIGHT?
This is a HEIGHT VELOCITY DIAGRAM, not an ALTITUDE VELOCITY DIAGRAM. right?
Chopjock, you do realise on what parameters full size aircraft performance is based on don't you?


… or b.
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Old 27th Jan 2016, 15:25
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Ok ..i accept that low flying may be inside the curve !! Im not sure why , as i would say that engine failure at say 30- 60knots and 10ft was a very easy auto to pull off . I do however accept that a turn to check behind before a towering t/o would be my method !
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Old 27th Jan 2016, 16:34
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Sid
Chopjock, you do realise on what parameters full size aircraft performance is based on don't you?
I was asking if there is any difference between the terms"ALTITUDE ABOVE TERRAIN" and "HEIGHT"
Because I have never heard of the term "ALTITUDE ABOVE TERRAIN" before.

I know the definition of ALTITUDE and HEIGHT, do you have an answer?
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Old 27th Jan 2016, 17:51
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Chop, are you getting confused with elevation?
'Altitude above terrain' is what it says, I can't see what you're missing
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Old 27th Jan 2016, 18:03
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Sid,
'Altitude above terrain' is what it says, I can't see what you're missing
So if "HEIGHT" is vertical distance above the surface and "ALTITUDE" is vertical distance above mean sea level, what the hell does"ALTITUDE ABOVE TERRAIN" mean?
That's what I am confused about.
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Old 28th Jan 2016, 11:49
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Just to say that I'm not ignoring you chop, still waiting to see if you've worked it out yet
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Old 28th Jan 2016, 13:12
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Just to say that I'm not ignoring you chop, still waiting to see if you've worked it out yet
"ALTITUDE ABOVE TERRAIN"
Yes, obviously"ALTITUDE ABOVE TERRAIN" means vertical height above sea level above terrain. LOL
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Old 28th Jan 2016, 13:23
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Devil

Ok ..i accept that low flying may be inside the curve !! Im not sure why , as i would say that engine failure at say 30- 60knots and 10ft was a very easy auto to pull off . I do however accept that a turn to check behind before a towering t/o would be my method !
And that's because you don't fully understand the definition of the dead mans curve Nigelh. How can a pilot call himself a professional pilot when he/she doesn't fully understand the dead man's curve??? I find this a common misconception with many civvy pilots.

Flying @ 20' 60kts in an MD500 would probably cartwheel an average joe and kill him. Reactions aren't fast enough.
In an R22 - 500' @ 30 kts will probably lead to a collision with the ground by the average abo if he/she doesnt react instinctively with the lever.

Having said that, to be fair, the definition states that the average pilot with average reactions suffering an engine failure inside the HVC will result in probable airframe damage at best, death at worst.
Even twin engine helicopters have HVC's.
Some scarey pilots out there....................................................
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Old 28th Jan 2016, 13:46
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Yes, obviously"ALTITUDE ABOVE TERRAIN" means vertical height above sea level above terrain. LOL
Throwing you a bone choppy;

Answer me this, What are the five different types of 'Altitude'?
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Old 28th Jan 2016, 14:20
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Ok so there's pressure, density,indicated, true and Absolute.
But the height / velocity curve is all about the height and velocity above the surface, right?
I agree if the air is thinner due to high terrain, that should be taken into account, but the graph does not show this.
So my point is the left side of the graph should depict height, as in vertical distance about the surface. So why does it say ALTITUDE? (especially if there are 5 different types!), and yet the Robinson H/V curve is in HEIGHT as it should be.
I guess MD really mean "ABSOLUTE ALTITUDE" instead of the term "HEIGHT"

Last edited by chopjock; 28th Jan 2016 at 14:49.
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Old 28th Jan 2016, 16:56
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Hey choppy; after all that, how is it that you don't have an issue with the term 'velocity'?
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Old 28th Jan 2016, 18:19
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how is it that you don't have an issue with the term 'velocity'?
If there were 5 types of "VELOCITY" I might!
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Old 28th Jan 2016, 18:53
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how is it that you don't have an issue with the term 'velocity'?
If there were 5 types of "VELOCITY" I might!
Pity for our listeners that there are only four
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Old 28th Jan 2016, 18:56
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Choppy babes:

Aviation altitude is measured using either mean sea level (MSL) or local ground level (above ground level, or AGL) as the reference datum.
From wiki for beginners.

Otherwise - I like your determination
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Old 28th Jan 2016, 20:35
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TC ..... I thought you were dead !!! I can only imagine that you were a sub standard Mil pilot or that now in your old age your reactions are very slow If you have actually done throttle chops at v low level you may understand ...... You are aware that when you fly ...you just fly the aircraft and react to changes of pitch etc automatically . You don't actually need to know you have had a failure , no need to drop collective with lightening reflexes . You just flare ....as much as you need to in order to keep height . If you would like a lesson from me I'm quite happy to teach you . Off course being a military God you probably never did crop dusting and never learnt the art of really low level . The crop dusting pilots on here could teach you a few things about HV curve and what's possible as they are flying in it all day long
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Old 28th Jan 2016, 22:31
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The crop dusting pilots on here could teach you a few things about HV curve and what's possible as they are flying in it all day long
Of course we all know that there's no problem flying in 'the shaded areas', much like flying over the sea beside the cliffs … until the donkey stops that is!
That is the moment when the shaded parts of the curve or statements like "within autorotative distance from land" come into play

Which is why we will read things in manuals, such as;

Use of Chart:
Caution:
Observe the cross−hatched regions of the Height Velocity Diagram.
These represent airspeed/altitude combinations from which a
successful autorotation landing would be difficult to perform.
Operation within the cross−hatched area is not prohibited, but
should be avoided.

Dance with lady luck too often and eventually she'll step on your toes
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Old 28th Jan 2016, 22:51
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Ok fine Sid... So you wouldn't crop spray , sling load , or winch would you ?? I think what you meant to say was that it is not a good idea taking unnecessary risks dallying in the HV curve unless you are doing a job that requires it Flying outside of auto distance of land is totally different and you should have floats !!
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Old 29th Jan 2016, 01:53
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.

SilsoeSid ... you remind me of the guy who goes to the airport and opens his hangar door.

The rule books are stacked to the ceiling but there are no aircraft .

.
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Old 29th Jan 2016, 06:32
  #80 (permalink)  

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Nigelh;
Ok fine Sid... So you wouldn't crop spray , sling load , or winch would you ??
I take it you failed to read the bit of my post that said;
"Of course we all know that there's no problem flying in 'the shaded areas', much like flying over the sea beside the cliffs … until the donkey stops that is!"
p.s. You forgot to mention, low level tactical flying, fast roping, abseiling, fire fighting, lake/river rescue, etc in your list

Flying outside of auto distance of land is totally different and you should have floats !!
So instead of having a go at certain people here, why don't you get out and spread the word around in your circle of influence?
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