Quick question for a Harrier driver, or JF
 

Unless this is classified.....:confused:

Not fussed about which version, and assume clean config, just curious as to what's the approx max ceiling in the hover......??

No reason other than to settle a 'bloke in a pub said' type arguement :p

I'm not a Harrier Pilot... But I played one once on the radio... :}

It's all about density altitude really... What's the temp and pressure at the location of your attempt? :8

Interesting question - since there would be no reason to do it (unless you wanted to vanish from your adversary's Doppler mode), has anyone ever hovered a puffer-jet higher than the starting point for the vertical landing descent?

Laddo was watching the thing with James May the other day obviously and so he chimes in with this absolute gem…..

A Harrier can only hover when close to the ground as because of levitation……

After composing myself and ceasing laughing I tried to explain that they only hover close to the ground as that’s really the only time they need to hover……

So, me thinking that messers Bedford, Merryweather and Farley etc must have tried a max altitude hover at some point during trials it would be easy to look up and point laddo in the right direction……but apparently not, hence I thought I’d offer said subject to those that might know or hazard an educated guess.

I vaguely seem to remember Harrier demos of years gone by when a rotating hover climb used to be done up to a few thou’ ish….??

Two separate issues here. A 107 engined jet will confortably hover at 3500-4000ft AMSL. However it's only easy to do this when you are close to the ground so you have some visual references to look at. (though physical interaction with the ground is of no relevance). So if you are at a high altitude airfield then no problem. Try decelling to the hover at 3500ft AGL and things are more tricky - no visual reference for position or drift and substantially stronger winds to consider - bearing in mind the IMD issues between 90-30kts - normally a recipe for a departure.
I have seen a jet VTO'd straight to circuit height before - but that was a calm day!
JF will be able to give you all the detail.

Stronger winds not an issue if no visual reference

Not interested in wind speed effects on holding a steady hover position over the ground, but on windspeed / relative airflow effects and the avoidance of intake momentum drag during the decel, ie being able to keep the vane straight vs available control power. When close to the ground its easier to "see" the wind direction and fly an into wind decel, or to visually correct during a cross wind decel, which I would aim to avoid much above 35kts, - at height it's harder to know if you are crosswind and the wind is stronger.....

Interesting question - since there would be no reason to do it (unless you wanted to vanish from your adversary's Doppler mode), has anyone ever hovered a puffer-jet ...

That wouldn't work with an up to date radar, L. O.

If not visual ground, then wind unless gusty is effectively zero in your hover transition.

ie you are hovering relative to the air not the ground.

And what's the RoC in vertical level flight?

I seem to remember there was a competiton; brakes off to 5000 feet, and the Harrier beat all-comers. Correct?

Given the same weight I think a Chinook would leave a Harrier for dead,even a Seaking.even with the brakes on

It's exactly zero.

This hovering away from the ground is obviously so difficult; how on earth do those helicopter pilots do it?

Shy Torque,

It probably doesn't matter to a helo if they are close to the dead stop hover so 30kts sideways at 3000ft is no big deal. Intake Momentum Drag in the Harrier means that either building up a ood deal of sideslip (or even too much reverse speed) can cause all sorts of problems.

Tourist.

So how can you tell when you're in the dead stop hover relative to the airmass around you? IAS stops indicating at 30kts and the vane ain't a lot of use.

From a technical / performance pov, the value and caveat given by SammySu above are consistent ;)

NoD

We really need JF here, but as NoD says, SS is spot on. Having tried to reduce to a semi-hover at height (to confuse my opponent:)) I merely succeeded in exceeding the yaw parameters and significantly confused myself as I dramatically fell, out of control, to the sound of much guffawing...............:)

Flap.

No argueing about the difficulty level of the hover, just pointing out that if you are not using visual references on the ground, wind is irrelevant.
In the same way that in a hot air balloon it does not matter once clear of the ground how much wind there is. 1 kt or 200 kts it is always calm in the basket.

Tourist - make yourself a coffee and have a quiet think about how much control you have over your airspeed in a balloon:)

BOAC,

I thought when you were on the Bona Jet the Montgolfier brothers were hanging out in Stamford. Is this why you know about balloons :O

General readers,

I too tried to exercise my amateur test pilot skills (all in the interest of learning my aircraft's capabilities you understand) and see when the donk ran out of puff. In the scenario suggested by SammySU (i.e. nil wind) I VTO'd and kept going up until I didn't any more (if that makes any sense). The mighty 104 engined FRS1 got to about 2500' before it decided to stop climbing. A similar experiment in a II+ got me to a decent shade over about 4000'. I think the latter would have been more impressive but I seem to recall the temperature being pretty high.

I'm not the owner of an ETPS strain guage, so don't know if these experiments (sorry envelope explorations) would be considered valid, but it might be enough for the original poster's question for the man down the pub.

BOAC

You miss the point.

Once in flight, the only things effecting the airframe are gravity and airflow over the airframe. Groundspeed and drift are aerodynamically of zero importance.
For example, if you have a 100kt wind and you fly into it at 100kts your groundspeed is zero but if you fly with the wind your grounspeed is 200kts. In both cases however, the aircraft will react in exactly the same way, with exactly the same accelerations if you pull back the stick.
This is basic relativity. We, and this goes for everything from a R22 to the Space shuttle(in the atmosphere!), fly relative to the air, not the ground
The only time ground has any relevance, is when we give it relevance by trying to land or hover by visual references for example. In these circumstances we are deliberately flying out of balance to match a visual picture.

In the example above when there are no visual references, I stand by my assertion that windspeed is irrelevant.

- actually, of all the things to talk about, that has the potential to kill you - sorry, T, but you need to do a bit of reading about the Harrier. Research JF's excellent article and re-read SammySu's posts, particularly #7? The beast is a bit different to R22s and Space Shuttles.

Pontius - I was a relative latecomer to the GR3, and by the time I got there, they had advanced to balloons with oars for propulsion and more 'interesting' things used to happen in Stamford:). Reckon your exploit was quite brave too! No sign of limiters tripped, perchance.....:ok: