"Boards Out"

Reason for flying with speedbrakes out
From: Richard
To: Tom
Sir, I am a Skyhawk pilot in an Asian country and which I have been posted this question. What is the REAL reason with flying with the boards out?

According to the NavAir, with a failure in speedbrakes, pilots are advised to raise their approach speed by 10kts.

Is it a US Navy tradition to ensure there's enough power for waveoff? Or is it because of the lift drag curve?

Thanks a lot
Richard

------ ( REPLY ) ------------

From: Tom
To: Richard

The real reason for originally flying the A-4 with speedbrakes out, back in the 1950s, was to raise the power setting of the engine during landing approach. The J-65 had a "flat spot" around 85% and was sometimes slow to accelerate through that power setting. Remember that the A4D-1 original basic weight (dry and clean) was only about 8950#, as I recall.

Some squadrons landed SB out while others landed SB in. Therefore when the A-4 training squadron (VA-125) got started on the West Coast at Moffett Field we had some instructors landing SB in (e.g. me), while others landed SB out. This was confusing to the Fleet Replacement Plots (FRPS). When NATOPS came along in around 1960 the landing procedure was standardized to SB out. Subsequently the J-52 engine came along and the "flat spot" went away.

One had to remember to bring the SBs in upon waveoff or else the advantage of the higher power setting was negated. Of course flying with SB out in the pattern costs a tad more fuel per pass. Wind over the deck, gross weight, and a/c configuration are additional considerations. Personally, I practiced both ways until I switched over to the A-7 in 1970.

Hope this helps explain how we got where we are with our little lady.

With best wishes,
A-4s Forever,
Tom

Note from Bud Southworth:
After NATOPs it became standard to put speedbrakes out on all jet aircraft approaches to landing --- field and carrier. There were many benefits to this and only wear and tear and higher fuel consumption as detriments.

As you intercept the ball on the boat you put the SB out to immediately enter a standard rate of descent that approximately holds the glideslope to the wires.

On a bolter you have a higher initial power setting and the SB coming in as the engine accelerates -- the total effect is quicker acceleration on the missed arrestment.

As you intercept the ILS, ASR, CCA or GCA glide slope you put the SB out to immediately enter a standard rate of descent that approximately holds the glideslope.

“According to the NavAir, with a failure in speedbrakes, pilots are advised to raise their approach speed by 10kts.”

Oh my, that sounds like a stupid Air Farce pussy response. Please consider that SB out or in has nothing to do with AOA (angle of attack) or stall speed -- its just drag. Remember that the whole point is landing --- and the faster you land the more chance you have of something bad happening ( hydroplaning down the runway, blowing a tire, overheating the brakes ) to name a few. Fly AOA L/Dmax, land on the numbers and you’ll be better off.

Bud Southworth