L-39 doing circuits at YBW Sept 18, 2017

[David MacRay]

I don't know how fast they were approaching but they were touching down pretty close to the numbers, possibly before them, and I don't think they were using half of the 5000' feet for their touch and goes. I am guessing they kept their rolling speed up to get airborne quickly.

I suspect they were not braking very hard on the full stop because they used much more runway for the roll out on that one. I was distracted but they may have went right to the end to exit.

Of course all I can offer is speculation since I was hanging out by the fence and did not talk to them.

It's interesting that when I got home and googled the registration, Flightaware listed the last flight as having landed two years ago.

[Colonel]

I was never a huge fan of touch and goes in the L39.

While I understand that you can get more landings in,
remember that all landings are full flap and that you
must select takeoff flap after touchdown, as you are
rolling down the runway at 100 mph, and hope that
the hydraulics work perfectly.

Because if they don't, you're in a world of hurt with
full flap on takeoff.  Or a split flap.  Or no flap, if
both decide to come up all the way.

Maybe I'm just a pessimist, but I really like full stop
landings on the L39 on a long runway that doesn't
require much in the way of braking.  Take your time,
taxi back to the threshold, come to a complete stop,
then put your head down and do your takeoff checks.

Maybe shit never goes wrong for other people,
but Mike Mangold was a lot better pilot that I will
ever be, and he's dead now because shit went
south during an L39 takeoff.

Keep in mind what else he flew in his career,
including Red Bull, Reno jet racing, and F-4
combat in Iraq.  Holy fuck.  Extremely high
risk.  You know he was a flight instructor, right?
And he would send his students solo by jumping
out of the airplane (with a parachute on).  This
is Mike:


[youtube][/youtube]


As an engineer, I don't expect much from
machinery.  Sometimes I am pleasantly surprised
when it actually works as advertised.

[David MacRay]

It's pretty cool to be able to read the perspective of someone who has actually flown one, even better since you are so good about using lots of details. Thank you.

Those fly bys were probably not even close by pylon racing standards but I suspect the perspective being inside the tower was intense. Especially the first one.

[mcrit]

[quote author=Colonel Sanders link=topic=7101.msg19226#msg19226 date=1505793486]
Gotta watch the brakes heating up, doing that.

There is a limit in the manual as to the number of
landings you can do per unit time - I forget the
exact number of the top of my head.
[/quote]


Why would a touch and go mess with the brakes?  I can see a limit on gear cycles per unit time (avoid heating up the hydraulic pump).

[Colonel]

My bad.  Manual refers to full stop landings.

[mcrit]

[quote author=Colonel Sanders link=topic=7101.msg19326#msg19326 date=1506037227]
My bad.  Manual refers to full stop landings.
[/quote]


Given that you have data for 62 (or so) different aircraft in your head I think you can be forgiven.....

[Colonel]

Couple articles I wrote, trying to de-mystify the whole jet thing:

[url=http://www.pittspecials.com/articles/FlyingAJet.htm]Flying A Jet[/url]

[url=http://www.pittspecials.com/articles/L39.htm]Flying the L39[/url]

As always, worth what you paid me for it, and anything else is a bonus  ;D

[David MacRay]

It certainly seemed possible it referred to touch and goes. Depending on who put the brakes back together last time they were serviced. Calpers typically don't have springs to pull the pads back. They could be draggy.

I think the full stop that I watched them do was probably not too bad on the brakes, they touched down early and rolled out to the end. They might not have used the brakes. I would guess they used a bit of brake but not as much as if they only had 3000'.