Extending air brake on approach
Buccaneer wing was also blown along the mainplane towards the leading edge..
Regarding the 'stick for speed' debate for real aeroplanes (not those ugly clattering things), I was originally taught to fly the Hunter at Valley and Brawdy using 'point and power'. However, at Honington we were required to fly the T7A / T8B Hunter (for Buccaneer training) using 'stick for speed' - which was totally alien to me after all my JP/Gnat/Hunter training. Control column selected attitude and AOA (-ish), with thrust controlling glide path descent rate. But you still had to make sure that your 'fixed reference' on the runway was correct. When the mirror aided dummy deck landing device was on, it was dead easy to control the glidepath accurately keeping the light in line with the greens using thrust (with the control column for AOA), but without such a 'glidepathometer', 'point and power' is a much more intuitive technique.
Last edited by BEagle; 17th Aug 2012 at 13:46.
How did I guess this thread would turn into a QFI wonderland? Real fighter pilots know that on the approach with airbrake out, it requires a higher throttle setting allowing an easier go around should it be necessary. Much easier to cancel the drag than wait for the engines to spool up!
Also keeps electrics and hydraulics on-line!!
Simples
PS How many colours of chalk does it take to do a briefing?
Answer, One!!
CFS............ at least six!!!!!!!!!!!
Chalk? CHALK?? How utterly last century, old bean.
4 x dri-markers - and don't get too pi$$ed on the fumes!
(Red for airmanship and, of course, L00KOUT!)
4 x dri-markers - and don't get too pi$$ed on the fumes!
(Red for airmanship and, of course, L00KOUT!)
Join Date: Jul 2008
Location: Australia OZ
Age: 75
Posts: 2,586
Likes: 0
Received 53 Likes
on
46 Posts
A-4E/F/G NATOPS says: "...Immediately after the break, extend speedbrakes and retard throttle to 70 percent. Speedbrakes will normally remain extended throughout approach and landing. (Speedbrakes increase the stalling speed approximately 1 knot.)
Optimum angle-of-attack approaches to touchdown will be made... Attempt to control meatball, lineup, and angle-of-attack/airspeed as precisely as for a carrier approach in order to maintain proficiency in this technique."
This A-4E/F/G NATOPS (my own copy scanned with added A4G bits) available here:
http://www.a4ghistory.com/A4G-NATOPS...Searchable.pdf (142Mb)
Optimum angle-of-attack approaches to touchdown will be made... Attempt to control meatball, lineup, and angle-of-attack/airspeed as precisely as for a carrier approach in order to maintain proficiency in this technique."
This A-4E/F/G NATOPS (my own copy scanned with added A4G bits) available here:
http://www.a4ghistory.com/A4G-NATOPS...Searchable.pdf (142Mb)
Join Date: Aug 2007
Location: Oz
Posts: 644
Likes: 0
Received 0 Likes
on
0 Posts
The USN Hornet F/A-18 A/B/C/D did not use speedbrake on approach due turbulence interfering with tail and whatnot.
The SuperHornet does not have a conventional speedbrake. [Which brings to mind is the S/B function used in Shornet on approach? I'd guess yes.]
Join Date: Jul 2008
Location: Australia OZ
Age: 75
Posts: 2,586
Likes: 0
Received 53 Likes
on
46 Posts
From F/A-18 A/B/C/D NATOPS:
"Airborne, when in the AUTO FLAPS UP mode, the speedbrake automatically retracts above 6.0 g or above 28° AOA and, when not in the auto flaps up mode, below 250 knots. For aircraft 161702 AND UP, the speedbrake extends with the flaps HALF or FULL so long as the switch is held in EXTEND. This is not recommended. The speedbrake operates normally on the ground."
F/A-18 A/B/C/D NATOPS diagrams are clear about retracting speedbrake downwind for field and carrier landings. This NATOPS available here also:
U.S. Navy F-18 NATOPS Flight Manuals | Public Intelligence
"Airborne, when in the AUTO FLAPS UP mode, the speedbrake automatically retracts above 6.0 g or above 28° AOA and, when not in the auto flaps up mode, below 250 knots. For aircraft 161702 AND UP, the speedbrake extends with the flaps HALF or FULL so long as the switch is held in EXTEND. This is not recommended. The speedbrake operates normally on the ground."
F/A-18 A/B/C/D NATOPS diagrams are clear about retracting speedbrake downwind for field and carrier landings. This NATOPS available here also:
U.S. Navy F-18 NATOPS Flight Manuals | Public Intelligence
Join Date: Jul 2006
Location: by the Great Salt Lake, USA
Posts: 1,542
Likes: 0
Received 0 Likes
on
0 Posts
With the A-4, just remember that the first 3 models (A4D-1, A4D-2, & A4D-2N... redesignated A-4A, A-4B, & A-4C) did NOT have the fast-responding Pratt & Whitney J52... they had the much more sluggish Wright J65 (license-built version of the Armstrong-Siddeley Sapphire 100), and so keeping the engine spooled up was far more important.
When the newer models came out, it was easier to keep the same procedure for all Skyhawk models, so as to avoid a situation where a pilot used to a later model forgets to ride the upper part of the power curve when flying an earlier model.
When the newer models came out, it was easier to keep the same procedure for all Skyhawk models, so as to avoid a situation where a pilot used to a later model forgets to ride the upper part of the power curve when flying an earlier model.
Join Date: Jul 2008
Location: Australia OZ
Age: 75
Posts: 2,586
Likes: 0
Received 53 Likes
on
46 Posts
All USN jet aircraft - until the Hornet - kept the speedbrake open for approaches for the same 'faster engine spool up response time' reason described earlier in the thread.
Last edited by SpazSinbad; 27th Jul 2011 at 09:03.
Thread Starter
Join Date: Jul 2011
Location: Over The Rainbow
Posts: 7
Likes: 0
Received 0 Likes
on
0 Posts
WHOA..the number of replies in just a day!
Definitely THE BEST forum ever..!!
The answer is clear now..haha
Thanks a lot for the insights/explanations/sources and personal anecdotes guys!!
Definitely THE BEST forum ever..!!
The answer is clear now..haha
Thanks a lot for the insights/explanations/sources and personal anecdotes guys!!
Thread Starter
Join Date: Jul 2011
Location: Over The Rainbow
Posts: 7
Likes: 0
Received 0 Likes
on
0 Posts
If you're on the wrong side of the curve, a decrease in IAS equates to an increase in total drag, which in turn decreases the IAS further and exacerbates the problem. The increase ZLD curve means that the bottom of the curve equals a lower IAS, so you can fly your original approach IAS but be on the "good" side of the drag curve, where a drop in IAS equals a drop in drag and hence the best chance of recovering your speed.
Sorry..but I need to ask, when you mean on the wrong side of the curve, do you mean that the thrust setting for the aircraft is insufficient for the aircraft to maintain airspeed?
Or does the 'wrong' side of the curve mean the left side of the curve (the curve being divided into left and right by the min. drag speed).
I'm still a little confused here.
Yes, wrong side as in the left side if we have EAS on the X axis and Cd on the Y axis.
On the LHS, a decrease in EAS corresponds to an increase in drag, which in turn exacerbates the drop in EAS, which in turn etc etc; hence a bad place to be, and very much the "wrong" side of the curve!
You'll need a lot of power to overcome the increasing drag and improve your lot.
On the "good" side of the curve, a drop in EAS equates to a drop in drag (because at these speeds, the drop in ZLD more than offsets the smaller rise in induced drag), meaning thee aircraft is more likely to help you keep it speed stable.
On the LHS, a decrease in EAS corresponds to an increase in drag, which in turn exacerbates the drop in EAS, which in turn etc etc; hence a bad place to be, and very much the "wrong" side of the curve!
You'll need a lot of power to overcome the increasing drag and improve your lot.
On the "good" side of the curve, a drop in EAS equates to a drop in drag (because at these speeds, the drop in ZLD more than offsets the smaller rise in induced drag), meaning thee aircraft is more likely to help you keep it speed stable.
Put simply, a graph of Drag v. Speed will have a minimum value. If the aircraft is flown below a speed corresponding to this value, it will be 'speed unstable' as a slight decrease in speed will cause an increase in drag, further decreasing speed. Prompt thrust changes are necessary to fly an approach in this regime, which is sometimes termed 'the back of the drag curve' or 'the wrong side of the drag curve'.
The drag curve is made up of 2 components, one of which is directly proportional to the square of speed ('zero lift drag') and the other of which is inversely proportional to the square of speed ('lift dependent drag'):
D=(AVē + B/Vē)
Simply differentiation to find the minimum value of the expression (dD/dV=O) will show that this value occurs where V is equal to the fourth root of B/A. Since 'A' increases with extension of speedbrakes, landing gear etc., the new value of B/A will consequently decrease and so obviously will minimum drag speed.
(5 Forward 6 Back, your post should surely read 'Drag', not 'Cd' on the y-axis?)
The drag curve is made up of 2 components, one of which is directly proportional to the square of speed ('zero lift drag') and the other of which is inversely proportional to the square of speed ('lift dependent drag'):
D=(AVē + B/Vē)
Simply differentiation to find the minimum value of the expression (dD/dV=O) will show that this value occurs where V is equal to the fourth root of B/A. Since 'A' increases with extension of speedbrakes, landing gear etc., the new value of B/A will consequently decrease and so obviously will minimum drag speed.
(5 Forward 6 Back, your post should surely read 'Drag', not 'Cd' on the y-axis?)
Join Date: Jul 2002
Location: East Midlands
Age: 84
Posts: 1,511
Likes: 0
Received 0 Likes
on
0 Posts
I remember seeing USAF B45 bombers that operated out of Sculthorpe flying round the circuit with the drag chute deployed, probably for the same throttle response reason
It's much clearer with a pointer, a whiteboard, 4 colour pens and 10 minutes to ask some questions of your student, you know.
Now, someone ask about adverse aileron yaw, or sea breezes?
Now, someone ask about adverse aileron yaw, or sea breezes?
I used to detest Met - it just gave Standards QFIs an excuse to deliver steaming heaps of utter bull$hit, most of which was just opinion. "Ask the f*****g Met man!", was my suggestion!
But it was sooo important to be taught about the Inter Tropical Convergence Zone, 'Willy willies' and the 'Horse latitudes' during Gnat groundschool...
- or world atmospheric circulation theory when doing the Bulldog A2 work up with those grumpy old buggers at Topcliffe...
The F-4 suffered from roll-reversal at high AoA ("Buffet = boots!"). Which, in the days before Pink Wednesday, gave people an innocent excuse to ask a certain, shall we say, 'rather camp' QWI "Sir, can you explain 'roll' reversal - I don't really understand it".....
But it was sooo important to be taught about the Inter Tropical Convergence Zone, 'Willy willies' and the 'Horse latitudes' during Gnat groundschool...
- or world atmospheric circulation theory when doing the Bulldog A2 work up with those grumpy old buggers at Topcliffe...The F-4 suffered from roll-reversal at high AoA ("Buffet = boots!"). Which, in the days before Pink Wednesday, gave people an innocent excuse to ask a certain, shall we say, 'rather camp' QWI "Sir, can you explain 'roll' reversal - I don't really understand it".....
Last edited by BEagle; 27th Jul 2011 at 09:50.
Don't forget Katabatic Winds and the T/Phigram!!
For those that never knew him, Chick was an A1 and OC Stds Flt at Cranwell. You would sit down having just given what you thought was a pretty good answer and explanation to a question and Chick would then proceed to demonstrate 3 alternative ways to answer the question, all of which were better than yours.
YS