The Buccaneer's Deck Takeoff Button – Seeking Details

I believe buccaneers flew themselves off the catapult automatically with the pilot collecting the thing together after his backside has stopped trying to overtake his feet. Perhaps that is what is meant? Video of an S1 launch I have seen certainly shows the undercarriage remaining fixed until well ahead of the ship and away.

I stand to be corrected, Vega.
On a similar note, the XW5?? numbered Buccaneers were renowned for having “Airy Legs” syndrome, in that they regularly had to return shortly after take-off, as the undercarriage wouldn’t retract. Of course the usual Groundcrew response to the growbag (pilot) was, “did you press the up button hard enough” ?

Many slightly underpowered aircraft need to “clean up” as soon as practical as they are single engine critical until Single Engine Safety Speed is reached where the aircraft can continue to fly on one engine. On twins with widely spaced engines, this can be even more critical at low speed as an engine failure may put aircraft at a speed/power combination where there is insufficient rudder/aileron authority (due to low airspeed over the surfaces and the size of the control) to maintain directional or roll control. This is known as Vmca speed. This requires the pilot to throttle back on the “good” engine to prevent losing control. As you can imagine, at certain weights, this means you stop climbing….or worse…..Commercial Air Transport rules have some very clear guidance for designers and operators to minimise exposure to these regimes. The Mosquito, for example, with two powerful engines, fairly well spread, is notorious for having a large “gap” between take off speed and Vmca; I think about 60-75kts (Take off approx 100kts and Vmca 160-175 its), made even worse by a relatively slowly retracting undercarriage. As for a heavy Bucc off a deck, I can see why you’d want to “clean up” quickly in case of a power loss, if only to perhaps give you a couple more seconds to eject. As Moggy warns though, showing off by pre-selecting “Up” and getting the microswitches to retract the gear is risky if the aircraft has a little gust that just lifts it off for a second…https://www.youtube.com/watch?v=-Cunaek9W24

Many thanks for the replies;-

Moggy
Weight on wheels switches are commonly used to preform quite a few functions on an aircraft, e.g. Ensuring radars are off, ensuring ordinance systems are safe, but also commonly it energises a solonoid in the landing gear selector switch to prevent Up from being selected while on the ground. Very unusually on the Buccaneer a guarded switch was added to allow this to be bypassed. I understand it was only for use on cat launches but some film of RAF Buccaneer take off show the Undercarriage retracting at the very point where the weight is removed from the gear.

Cabbage
The undercarriage selector switches are on the left hand side panel. These consist of two switches, one above the other, the top push button is UP and bottom one is DOWN. Below this is the emergence lower button. On the port cockpit wall there’s is a gaurded switch which is the Deck Takeoff Button. I have pictures of this guarded switch installed on S1, S2, and S2B aircraft. At some point in the Buccaneers service life an instruction was issued to wire lock the guard closed to prevent its use. It’s also possible that a mod may have issued to remove it all together.

Just speculating.

Where a system using squat switches is installed it is possible to select gear up and, while the weight of the aircraft is on the gear it stays extended. But as soon as the aircraft is airborne the gear will retract.

But setting the aircraft up like this is a very unwise thing to do in aviation generally as hitting a small bump or a particularly strong gust that gets the aircraft off the ground temporarily then ruins that take off, and your entire day. Not to mention the aircraft.

But on a cat launch?

Moggy

I don’t remember seeing or being told about such a button on the Mk.S2B’s in RAF service. I worked on the Mk.2’s at Lossiemouth, and I’m sure would have been told of such a button, while attending ground school, or before entering the cockpit.

Many aircraft have systems operated by microswitches on the u/c that prevent retraction when the gear is compressed by the aircraft’s weight.

It’s not hard to imagine a similar system operating in reverse mode.

Moggy