Yeah, KMMU Tower give winds a couple times in the few minutes prior; first 310/4G16, and when the Lear was on (short?) final 350/8G16.
Lear 75 at Morristown KMMU
- Thread starter SteveC
- Start date
Cherokee_Cruiser
Bronteroc
Morristown Tower be like, winds 340@35G45 , instantaneous winds 230@5 knots, Runway 23, cleared to land.
Cherokee_Cruiser
Bronteroc
Just an Aspen joke
CFI A&P
Exploring the world one toilet at a time.
Im just going to guess that the Lear 45/75 series is prohibited from operating on other than paved surfaces.
knot4u
Repeat Offender
I've been involved in removing/installing the wings on almost all of the Lear models, the exception being the 45/75 series. If they were still constructed like the older models there's literally 14 (if my old brain remembers correctly) structural bolts that attach the wing to the fuselage. I can't imagine that a LR75 has accumulated enough time/cycles to warrant removing the wing so if there was an issue I'd suspect it was when the wing was installed initially, which I consider highly unlikely. Removing and reinstalling the wing isn't an everyday sort of event. The wing is one piece and you remove the engines to use the beam as a support for the aft fuselage then you remove the MLG and the keel. At that point you can raise the fuselage and lower the wing on a dolly to remove it after you remove either a tip tank or a winglet so you can slide it out from underneath the fuselage. It's a big job, but apparently there's a faster way of doing it. I suspect if the wing hadn't seperated the outcome for everyone on board would've been a lot worse.
Pilot Fighter
Well-Known Member
It doesn't surprise me at all. Components are designed to a meet a failure threshold which rarely includes maintaining integrity in a crash. Also, many components are strong in compression and weak in tension, or vice-versa. Some components are strong in shear and some are not.
Think of landing gear. Measure the forces (DVAF) in a drop test and then apply the same forces in the opposite direction and the gear will come apart with ease.
CFI A&P
Exploring the world one toilet at a time.
Excellent description that I was alluding to in my post. Just because the Lear has landing gear, doesn't mean it is designed to operate on unimproved surfaces like a Skywagon or Maule would, especially at high speed.
With enough force, especially in the opposite direction as intended, anything will fail.
tlove482
Well-Known Member
No, only aircraft, vehicles and people.
Pilot Fighter
Well-Known Member
If it's alive and not a person, it's FOD.
dustoff17
Still trying to reach the Top Shelf
This makes sense. As @Pilot Fighter posted above, the attachment point has designed “break away” parts.
For example, the majority of the Citation wings are held on by 4 bolts; they can handle just about anything we could possible throw at them from the cockpit. The attachment points for these bolts are equally strong in the vertical. However, they are designed to shear at a certain load when twisted (imagine if you will a wing tip digging into the ground).
This allows the energy to be ”absorbed” by the material rather than the occupants. Imagine again this amount of sideways G-Force energy being apply to the human body. Aortas and brains hate this kind of thing…..
knot4u
Repeat Offender
Agreed.
DropTank
Well-Known Member
Just saying, when looking at structures, never look at the tail attachments if you're a pilot.
Especially t tails and stableators.
I know they are engineered and tested but, damn!
dustoff17
Still trying to reach the Top Shelf
Or the wing of a 777 in flight…….
Now way, I’ll take a scoop of strawberry flavored please!
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knot4u
Repeat Offender
I've actually removed the horizontal and vertical stabilizers on a few jets. Other than a Hawker (we won't go into the horrible machinations required to remove to the fixed horizontal, the top of the tail comes off first) most horizontals are just a couple of pivot points and jackscrew points, usually ending up in at least three hard points, although unless you have a really high ceiling or an overhead crane you're going to do it outside with a truck mounted crane. Problem with going outside is weather, a Gulfstream horizontal is about 24' span and 24' above the ground, and it probably weighs close to 10,000 lbs with the elevators on. Imagine wrangling that thing with ropes tied to each tip while installing the pins (.0010" clearance on each) with a slight breeze. Never watch slow motion video of the jet you fly landing with the thrust reversers deployed. The vertical is a whole other animal, that's a BIG job and you want your best people on it. You also want those same people to start and finish the job. There are I think around 100 structural bolts holding the vertical to the fuselage on a Gulfstream, when we remove it we take out just less than half of them. What has always struck me is people who are very excited to get the job started (usually management) that haven't considered where to place these pieces and consider them as an inconvenience when they take up half of the hangar. Oh well, I hope I never have to get that deep again, I'm old.
DropTank
Well-Known Member
The second you said Gulfstream, Horizontal Stab, and Outside I winced
NO (expletive deleted) thank you!
Also, EXACTLY! pivot point and jack screw. That's it. anything goes, you die.
I know it works, I even understand the engineering and I still don't like it.
I just don't look at it anymore and make believe it welded on or cast in one piece.
DropTank
Well-Known Member
Or the wing of a 777 in flight…….
Now way, I’ll take a scoop of strawberry flavored please!
Or the engine in turbulence.
(slowly closes window)
knot4u
Repeat Offender
How do you like me now?