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MJP
18th Aug 2003, 08:20
Can anyone tell me where I can get info on the web (downloadable file) on the how-to-do the Jacobsen Flare ?

All I know is that Capt Jacobsen used to fly for Australian Airlines and his technique to judge flare at landing, has made life safer for flying instructors who have been teaching non-English speaking students here in Oz.

Thanks in advance :ok:

Traffic
18th Aug 2003, 11:39
MJP

There was a detailed article on this subject in 'Australian Flying7 12-18 months ago. You may find it at your aero club if they keep back issues.

I will dig it up from my files when I get home and give you the exact month.

Disco Stu
18th Aug 2003, 11:45
MJP

Last time I saw Dave he was doing his stuff weekends at PCK with the Air Cadets or Air Training Corps or something along those lines.

It was a while ago but you might still find him there.

Disco Stu

tinpis
18th Aug 2003, 13:22
Facing the front looking out the window and pulling back on the stick worked for me for 30 odd years ...theres another way???:}

Traffic
18th Aug 2003, 15:11
Tinpis

The Jacobsen Flare is based on your tried and tested methods but with the added bonus of forcing you to do differential calculus and complex trigonometry at the same time.

It is best executed while whistling the Jacobsen Flare theme song (adapted from the sound track for Apocolypse Now).

Also to help you focus, place a firecracker between your legs and light it as you go over the piano keys. If all goes well, this will induce a loud scream at the moment of impact. If it doesn't go so well you still get the loud scream but won't notice the rough landing.

Whoever said counting to three and using some hand and eye coordination was the easiest way to do it!!

tinpis
18th Aug 2003, 15:19
:uhoh:

Also to help you focus, place a firecracker between your legs and light it as you go over the piano keys. If all goes well, this will induce a loud scream at the moment of impact. If it doesn't go so well you still get the loud scream but won't notice the rough landing.

As an old checker used to say after one of those..."neat but not gaudy..":ok:

Traffic
18th Aug 2003, 16:05
....like a bull's bum sown up with a bicycle chain...

is, as I recall, the balance of the quote...as passed on to me by my old man!!:ok:

Traffic
18th Aug 2003, 22:41
MJP

It was an article entitled 'Perfect Landings' and it was in the March/April 1998 edition of Australian Flying.

Good luck with the hunt.

Woomera
18th Aug 2003, 22:56
Traffic

Perfect Landings?

I think I did one of those once, it's a bit like golf isn't it, just when you think you've got the slice out of your drive, it turns into a hook.:cool: :p

"Please remain seated whilst the Captain taxies what's left of our aircraft to the terminal.":uhoh:

Traffic
19th Aug 2003, 07:33
Woomera

Lost balls and now Hookers and Slicers. About sums up the world of aviation I would have thought

:confused:

MJP
19th Aug 2003, 12:00
Dear Traffic, Disco Stu, Woomera et al,

A grateful thanks for your help & humour from this trainee flight-instructor. Let's see If I can find a 1998 copy of Australian Flying SIGH. :{

I got started down this track doing some research into the question: "What is a GOOD LANDING?". Specifically, is a "greaser" a good landing? Or is a positive/firm touchdown at/close to a nominated point, using the proper profile a good landing?

I did my CPL at RAAF Point Cook, with a decidedly military flavour, so we used the power & point approach (ie power for airspeed control; control column for aimpoint position), and had to land near/at a nominated touchdown point - greaser was a nice-to-have.

I've read the CASA Day VFR Syllabus (Unit 19. 1 - Land Aeroplane (CPL)) to look for guidance and it looks very military in its requirements. Horses for courses and I'm used to what I got in the RAAF, but I'm flexible. I realise that the RAAF techniques are closer to what the airlines require

So guys, any hints from you as to what to teach in the "real world" of GA to my future students. I go back to my original question: "What is a GOOD LANDING?"


Aye,


MJP :ok:

Ralph the Bong
19th Aug 2003, 14:22
There are 3 neccessary elements to a good landing ; 1)a stable approach, 2) Flare and cut thrust at the correct height, 3)nobody really knows what the third one is...:p The Jacobsen techique relies on being stable (that is: on speed, on slope and with a constant sink rate) and with flare and power reduction initiated when a fixed point on the RWY disappears under the nose. This fulfills criteria 2). On the B747, this is when the first centerline after the piano keys is lost from view. For the B767, it is when the first center marking before the 300m marker disappears. This can be a bit tricky at night! The actual 'skill' part comes from judging at what rate to flare and pull off power. This depends on the conditions of the day (wind, density alt., AUW).I do not know the flare points for GA aircraft, but someone will. A good landing is a SAFE landing. If the touchdown is smooth and halfway down the runway or off-centerline, than it cannot be seen to be safe, can it? A firm touchdown is desirable if the RWY is contaminated with slush or standing water, so as to break the surface tension and not aqua-plane. Thus, a hard landing is not neccessarily a bad one. The Jacobsen technique is very useful for getting the aircraft to the correct touchdown zone on the RWY, but what happens in the last 3 feet is in the lap of the Gods. :D

BrianG
19th Aug 2003, 16:15
My flying instructor, who is an old bush pilot (and aerobatics instructor - yeh ha), taught me from abinitio "the proper way" - and was at pains to point out that he was required to teach the Jacobsen Flare method to the uni students he also taught and he disliked the method. His thoughts were that the Jacobsen Flare method made it easier & less expensive to train pilots and was at the expense of proper landing technique. I don't know where the truth lies, and haven't flown using the JF method, but I do have respect for my flying instructor.

Traffic
19th Aug 2003, 17:24
MJP

If you cannot find it PM me with your email address and I will scan it and send to you.

Ralph the Bong has given a good summary without the trig. Brian G also makes a good point. God still has a role to play in aviation! Better firm on the numbers than a greaser into the fence.

I suspect Jacobsen by numbers is more relevant to heavy jets than GA.

T3000
19th Aug 2003, 17:53
It works. with a stable approach. lots of patience. Used it for a year while instructing. Had switched on students first solo in 7-8 hours.

MJP
20th Aug 2003, 18:38
Guys,


Thanks for the input; I wish that some of the guys I fly with spend as much time thinking about what is a good landing.

Close to home, its pretty sad when you see a continuous stream of C172s and PA28s doing circuits, at a local military airfield; floating with too much speed and landing apparently with power on to get that "greaser".


I reckon the following quote from the U.S. Navy's Approach Magazine (May '82) says it well:-


[COLOR=blue]It is a true confidence builder when a pilot can make a landing nose high; on centreline; in the first 1 000 feet of the runway, with zero thrust at touchdown. When he can combine a "great" landing with a soft touchdown, the multi-engine pilot will experience a feeling so good it's almost indecent. And do you know what the best part of it is? It'll be a SAFE LANDING with PROPER PROFILE TECHNIQUE[COLOR=blue]

Aye,

MJP

moosp
20th Aug 2003, 22:19
I find it amazing that an individual can take a technique from the Boeing Flight Training Manual, put it into his own words and then call it his own.

The so called "Jacobsen" flare has been standard operating procedure in some airlines for 20 years that I know of and probably longer than that. The power of Pprune to put your name to something!!

I propose the "Moosp Touchdown" which occurs when the pilot concerned forgets to flare a Boeing jet and presents the rubber jungle to the passengers. There, now its mine!

"Traffic" has it with more humour than I but you begin to see the point...

Paul Phelan
21st Aug 2003, 14:18
There were two articles, one in Australian Flying Mar/Apr 98 and the other (Similar but not identical) in Flight International 18-24 Feb 98. I tried it in a Trike the other day and It didn't work because I pulled (as in aeroplane) instead of pushing (as in Trike.) If David J's out there I'd like to see him try it in a Trike!

BrianG
21st Aug 2003, 15:45
Paul,

I liked your article on flying a trike. Lane Wallace (?) from the US Flying mag wrote in the last issue I received about her experience in flying a trike. From memory Lane flew the same type you flew - the ones manufactured at Redhead, a suburb of Newcastle.


MJP,

The issue the JF would seem to be demonstrated in the following story. Sometime ago a friend of mine (now flying 747s for an international carrier) picked his father (then a senior check pilot with Qantas) up from Bankstown in a Warrior, intending to land at Mascot. Eager to impress his father he made sure the flight went smoothly. And it did - until very very late final @ Mascot his father became very tense. The height at which his father became tense was about the height he would normally have flared a 747 - much higher than the flare height of a Warrior. His father had not flown in light aircraft for years.

Woomera
21st Aug 2003, 16:21
And with ol "wide runway" effect as well I'm sure he would have been.

MJP
21st Aug 2003, 17:08
I seem to recall that even the "Crash Comics" did an article on the Jacobsen Flare. I can't remember the edition, but the cover had the photo of an F-28(?) taking off/landing towards the viewer(?) framed in a thick green border possibly from 1985? I wish I hadn't thrown that edition away!

Paul,

It's interesting that you tried to use JF in a trike, because I want to use try it in a Jabiru to keep in my instructor "bag of tricks" to try if students are having problems with landing. If you read this I'd be happy to get your comments using JF for low-interia aircraft.


MJP

Disco Stu
21st Aug 2003, 18:32
moosp, I don't know the basis for your " I find it amazing that an individual can take a technique from the Boeing Flight Training Manual, put it into his own words and then call it his own".
and
"The so called "Jacobsen" flare has been standard operating procedure in some airlines for 20 years that I know of and probably longer than that."

I'd like to add that I flew with Dave in the mid 80's as he was developing his technique, we tried it in Cesspits, Paupers, a Banana and an Airtourer. The last time was in the jump of a TN D9S on to SY rwy34 (no left or right in those days).

I'd appreciate to know the basis of your comments.

Disco Stu

rmcdonal
21st Aug 2003, 18:47
Tell you what.... I don't know about all this fancy landing stuff, If I get it down on the back wheels it's good, If the back wheels are on the runway even better, If the back wheels are still attached to the plane then its a 100% perfict.
:ouch: :ouch: :ok:

MJP
22nd Aug 2003, 08:06
Disco Stu,

I once had the opportunity from Dave to show me the JF, when I was doing my CPL training at RAAF Point Cook Flying Club (early 1990s). I seem to recall that he had developed a presentation of the JF technique on large pieces of cardboard(?) to show people who were interested.

I admired the fact that he did not try to sway me from my own technique; but he offered his as an alternative if you were interested.

I wish now that I had flown with him because his technique could have been useful for students with landing problems.

I've heard that some flying instructors teaching student pilots from Sth East Asia, have used it to teach landing effectively. Anyone who has actually done this care to comment?:cool:

Paul Phelan
23rd Aug 2003, 20:11
MJP,

I tried to e-mail you a response but the message bounced back with words to the effect that your e-mail address wasn't on their current database.

MJP
24th Aug 2003, 13:05
Paul,

I've sent you a private message with another e-mail address: sorry for the inconvenience. Ta again for your help.

MJP

Paul Phelan
25th Aug 2003, 06:32
MJP

I can't figure out how to receive e-mails in this system, and anyway when I tried to put the scanned images on a Word file they were too big to be transferred. Why don't we go back to the dark ages? I'll get the things photocopied and mail them to you if you send me a postal address. But don't send it through the PPRuNe system, just send an ordinary e-mail addressed to [email protected].

Cheers