What was it?
 

Just seen a helo fly overhead Bicester with what looked like crop spraying attachments either side (sticking out each side about 2/3 of the rotor disk radius).

Seems a bit too expensive an option for crop spraying so any ideas ?

One of these......??










http://www.pbase.com/kbmphotography/image/31655193.jpg

I'll get my coat........:D

Ha-Ha, he's on fire! :D :D

it sounds like the 355 that is doing the digital mapping contracts

Does this help?

Does this mean the contract for enforcing the GM crop ban has gone to an overseas operator ?

Cheers SD

It looked very like G-TOPS but the booms/pylons came out horizontally

On the Military Helicopter shown in previous posts could anyone explain what the two 'Microphone' like objects are on the end of the 'booms' that stick out from the sides of the engines(?) roughly in line with the observer's/navigator's chin?

One is upside down and the other the right way up. I just have to know.

Thank you in advance.

Don't know about the UK, but in the US helicopters are routinely used for crop spraying, especially orchards, etc, where the chemical needs to get under the leaves. The rotorwash helps with this.

No worries collectivefriction... Can't help you any more than that though.

I believe they measure the wind velocity (hence their different positions). For what purpose I can't quite recall. Missile firing? (That's a technical term, by the way!) Someone will know...

Air speed / direction for the missile control systems.
(or so I was told by the Italians at last year's WSM helidays)

I would have thought that the downwash played havoc in that place but I expect there are some very fancy electronics/computers behind the probes.

It could have been on a bracken spraying mission (popular at this time of year). I saw an R22 thus equipped at Oban three weeks ago. Two horizontal booms & an underslung flat tank. Most perkuliar mama. (came from Thruxton, which I guess is en route from Bicester ...)

h-r:cool:

The two 'things' on the opposite sides of the pylon on the AH-64 are indeed airspeed sensors. They incorporate both pitot information and angular information to provide a relative wind signal to the fire control computer.
Since there is relatively little change the longitudinal or lateral CG with fuel burn or armament expenditure on the Apache, it's pretty easy to get accurate, repeatable information this way.
The helicopter is hovered against a known groundspeed and relative wind azimuth pace truck (this is a lot of fun) and the system is calibrated for downwash velocities and angles from the two sensors. When the system sees that in those angles and velocities in real life, it knows what the relative wind direction and speed are, and can make appropriate corrections to the fire control solution to give first round hits.
On the AH-64D, these replace the rotating low airspeed sensors on the top of the mast that featured on the AH-64A. The AH-1S had a similar single swiveling pitot tube. The HH-65 had a rotating pitot on the top of the mast. The A129 has a single swiveling pitot tube. The South African Rooivalk also had a rotating pitot tube system.

So much for trivia....how's about the three wires dangling from the aircraft? One adjacent to each missile and one on the left main gear (pilot's view).

Ah, those are easy.
The ones dangling from each missle are, in fact, dangling from the horizontal stabilizer and are static discharge wicks for continuously discharging static during flight. The one dangling from the left main tire (tahr in Texican) is also a static discharge wick - since the main wheel touches down first (hovering left wing low), it discharges the static built up during flight on touchdown. A lot of helicopters with wheels have these - some on the tailwheel, some on the mains. The tires insulate the airframe from the ground, in theory.

....and the one sticking up above the Radome?

...that's the lightning conductor...;)

Now I am confused...."the two continously discharge static in flight"....but the one on the main gear discharges the static built up during flight upon touchdown?

With this application of active static wicks.....does one have to "earth" the aircraft when it is parked in the hangar or parked on the ramp?

Where's Rich Lee when you need 'im!!?!?!?! :)

Now.... there I was over Field 21B at 50 ft in the auto hover.....!!

(P.S. Real men where blue when they fly!!! :))

http://www.pbase.com/kbmphotography/image/64220690.jpg

Sorry chaps, still a bit confused.

I think I understand that: fired projectiles with no inherent guidance mechanism (e.g. a bullet) need an allowance for prevailing wind for targetting.

Shawn's explanation (keep in mind I am ballistically challenged) seemed to say that the 'extra' pitots acted as sensors for the detection of the shifted downwash caused by external forces thus yielding a factor for use by the fire control solution.

If my para 2 is correct why would missiles require correction - do they not have inherent guidance?

Bit out of my depth here but indulgance appreciated.

Those missiles are fired by applying an electrical charge to their @sses. (Light the blue touch paper and stand clear)

If some trooper came up to the aircraft as it landed, and touched the rear of the rocket, the static discharge could set it off. Hence, the discharge wick.:ooh: :sad: :eek:

Thats what the Army gets for doing away with hobnailed boots....course the sparks that are emitted by those soldierly foot stomping rituals they have would be as great a risk as the static.

Cron:
The missles have guidance, but still need a bit of help in the part immediately after launch. The rockets and cannon are pure ballistics devices and need to have windage compensated before they get sent on their one-way trip.
The swiveling pitot tubes give the corrections to the fire control computer so the system can make those corrections. For example, the crew wants to hit a target in the distance - they put the dot on the target and select the cannon. The fire control computer points the cannon at the correct place to correct for windage, sideslip, phase of the moon, transit of Venus, etc, and rounds hit the target first shot.

SASless:
In theory one should ground skid equipped helicopters in a hangar also, but the skids do a great job of grounding. For wheeled machines, yes you do need to ground them.