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Brewster Buffalo
3rd Mar 2019, 19:08
As we know the Buccaneer had a Boundary Layer Control system whereby bleed air was sent to the wings,and the tail thereby reducing take-off and landing speeds by 25 knots.
Once the Buccaneer became a land based bomber was any thought given to doing without this system? One website gives the take-off as 3,000 ft with BLC and 3,700 ft without - was that 700 feet vital?

Terry McCassey
4th Mar 2019, 06:37
Useful for carrier ops. I would suggest

PeterJG
4th Mar 2019, 09:07
Take-off on land was always without BLC and flap/droop/tailplane flap 15-10-10, except the very odd occasion on a short runway. BLC was always used for normal landing flap/droop/tailplane flap 45-25-25, although unblown 45-10-10 was available with a higher landing speed. Remember the Bucc had no tailchute or reverse thrust and was quite heavy!

chevvron
4th Mar 2019, 09:19
Had a Bucc Mk 2 (pilot Mike Brooke) departing one day when a Lightning called initials.
As the Bucc called 'rolling', I reminded him of the Lightning running in for a break, to which the Lightning pilot (super guy called Jack Frost) said 'do you have to give the game away'? followed by a massive bang as he engaged afterburners.
The Bucc accelerated so quickly it took about 5 miles for the Lightning to catch him.

dook
4th Mar 2019, 14:32
Are you expecting me to believe that ? I wasn't born yesterday but I have flown the Lightning and knew Jack (Ian).

The Lightning at initials would be around 2-3 miles away and about 400 kts.

That Buccaneer must have accelerated faster than a bullet !

Pontius Navigator
4th Mar 2019, 15:56
Dook, OTOH I was told about a PI F4/Bucc.

Bucc doing warp 6 on the deck, F4 closing at warp 7. Bucc applies hard bank, F4 copies, Bucc continues in straight line turn rate so slow 😁

dook
4th Mar 2019, 16:19
Now that story I can believe.

Brewster Buffalo
6th Mar 2019, 10:59
Thanks for the replies.
My question arose from reading Keith Wilson’s “Haynes” manual on the Buccaneer which quotes a pilot saying ..“Once below 300 knots the handling qualities became quite different…..the aeroplane would bite back in a most unforgiving manner…..essential…one had the correct blow pressures….(and) that the tailplane flap moved upwards at precisely the same rate as the ailerons drooped downwards..”

If BLC was switched off was the Buccaneer easier to handle when landing at an airfield?

PeterJG
8th Mar 2019, 17:18
The relatively high wing-loading gave the Bucc its legendary ride and control at high speed. However, as with all similarly configured fast jets, at low speed without flaps etc, manoeuvrability was reduced and some care was necessary. That said, we safely did air-to-air refuelling below 300kts. Once confident in the approach configuration pilots could fly quite tight circuits using up to 45 degrees of bank, and with the precision needed for deck work. On the flap/droop/tailplane flap situation: the flaps and aileron droop were hydraulic, whilst the tailplane flap was electric. The same selector worked aileron droop and tailplane flap. If the ailerons were drooped and the tailplane flap failed to travel, the aircraft became seriously nose down out of trim. Hence on selection it was vital to monitor travel on the “cheese” indicators and to select only one stage of flap/droop at a time. An unblown landing at 45-10-10 was no problem on normal length runways, just a bit faster.

BEagle
9th Mar 2019, 13:14
"15-10-10...moving together, stop together" How I remember that - and if a pilot forgot to say 'moving together" PDQ, the navigator would immediately call "Check cheeses!".

Simulator training was very comprehensive, but coping with a pairs night VRIAB and going through the rigmarole of reconfiguring below 300 KIAS, including changing hands for the aileron gear lever, setting the autostabs to low speed, then from clean to 15-10-10, gear down, 30-20-20 check cheeses and blow gauges, 45-25-25 check cheeses and blow gauges...all with their own limiting speeds and trying to keep spaced on the leader, well, that was pretty darned demanding for an ab initio student!

LOMCEVAK
13th Mar 2019, 23:00
BB,

I don't have any Buccaneer manuals to hand but from memory ...

In answer to your original question about take-off, you have to consider the unstick speed as well as the ground roll because you have to consider the rejected take-off and the stopping distance available. A blown 30-20-20 take off had a much lower unstick speed than an unblown 15-10-10 one, as well as a shorter ground roll. Therefore, on a relatively short runway, especially one without an overrun end arrestor cable, the margin between stop speed and unstick speed was much less for a blown take-off than for an unblown one. However, once airborne on a blown take off there was a margin of about 20 kts before a safe single engine flying speed was reached during which the only option if you had an engine failure was to eject. With an unblown take off you had safe single engine flying speed from unstick unless you were very heavy, high and hot; that is why unblown take-offs were the preferred option.

On the approach, datum speed for a given weight was 19 kts faster unblown with 45-10-10 than blown with 45-25-25. The problem blown was that if you throttled back even to minimum blow pressure (20 psi) you would have a very high rate of descent if you stabilised, and if you were fast and wanted to slow down you had to respect this minimum blow pressure. Also, you did not have sufficient thrust for a single engine approach. You could fly blown 30-20-20 and this was only 3 kts faster than 45-25-25 and you did have a single engine capability, albeit with relatively poor go-around capability. Therefore, if single engine the preference was to fly a 45-10-10 approach. Another relatively obscure case (and it did happen) was that if the airbrakes failed to open using the normal selector you either had to use the standby selector, which put the hydraulic system into emergency generating a lot more problems, or fly a 45-10-10 approach with the airbrakes closed because to fly the correct datum speed you could not use sufficient power to maintain the blow pressure if 45-25-25 or 30-20-20 without the airbrakes being open.

If you had a double generator failure you lost the 'cheeses' and so had to approach 45-0-0 which was 10 kts faster than 45-10-10; we did practise this and it was not difficult to fly, just fast (but then a Tornado in 67 wing approached at around 220-230 kts!). On my first landing at Gibraltar I had a 'cheese' failure and ended up 45-8-8. This concentrated the mind and, with maximum braking, I stopped in about half the runway length (ie. 3000 ft) so there was no real drama.

What a great machine to cut your teeth on! Happy days.

Brewster Buffalo
15th Mar 2019, 19:29
Thanks Lomcevak. I can see continuing to use BLC, even when it wasn't needed, offered the option of operating from airfields with shorter runways.
Fine aircraft and, if the UK hadn't managed to get partners for MRCA, perhaps it might, in an updated version, have served with the RAF for much longer.