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edetroit
10th Mar 2023, 09:08
What is that inside the green circle on the B717 MLG door please?


https://cimg1.ibsrv.net/gimg/pprune.org-vbulletin/1072x501/335309591_969160750907434_1613198353104939658_n_bd22567e42eb 4cc52537cba5748dea134a552ce8.jpg


Regards

Ed

dixi188
10th Mar 2023, 09:43
Looks like a rubbing strip so if the gear doors are not closed they will touch the runway and the strip will wear away rather than damage the doors.
It was like that on the BAC 1-11 and if the gear had been lowered by "Free Fall" the doors stayed open.
Same era and similar design. (DC-9 and BAC 1-11)

edetroit
10th Mar 2023, 13:43
Thank you for your reply dixi118. What you said makes sense to me.

Regards

Ed

Rt Hon Jim Hacker MP
10th Mar 2023, 20:10
Was fitted to the Mad Dog. There to prevent damage to the doors when lowering gear on the emergency system. Amazing what you can remember from 30 years ago.

pocker pipty
10th Mar 2023, 21:56
You are quite correct

edetroit
10th Mar 2023, 23:25
Thank you guys for your help.

Regards

Ed

john_tullamarine
11th Mar 2023, 03:49
Later there was a mod to permit retraction. I recall one incident, alternate extension, door separated on touchdown, down the gullet, and a very expensive exercise overall ....

hikoushi
12th Mar 2023, 09:59
Canít remember the name of the material that bumper is made of, but recall being instructed to avoid touching it on the exterior preflight due to skin toxicity. Guess rubber wasnít good enough!

Check Airman
12th Mar 2023, 16:05
Nothing to add, but thatís a very clean airplane!

NISHTA
15th Mar 2023, 15:19
https://cimg5.ibsrv.net/gimg/pprune.org-vbulletin/1024x780/0275298_4bcc4203e876178b6702f6b9b6efd62126fd60bb.jpg

HOVIS
15th Mar 2023, 15:27
https://cimg5.ibsrv.net/gimg/pprune.org-vbulletin/1024x780/0275298_4bcc4203e876178b6702f6b9b6efd62126fd60bb.jpg
On the BAC 1-11 that was how you serviced the hydraulic reservoirs and brake system accumulators. I only worked on MD80s briefly so no idea if the architecture is the same.

bafanguy
15th Mar 2023, 15:54
Speaking of 717 tech issues, see the Twitter link in this article:

https://www.aerotime.aero/articles/video-shows-delta-air-lines-boeing-717-leaking-fuel

717tech
16th Mar 2023, 00:18
On the BAC 1-11 that was how you serviced the hydraulic reservoirs and brake system accumulators. I only worked on MD80s briefly so no idea if the architecture is the same.
Opposite for me. But yes, that's how the HYD system is serviced.

EXDAC
16th Mar 2023, 01:03
Speaking of 717 tech issues, see the Twitter link in this article:

https://www.aerotime.aero/articles/video-shows-delta-air-lines-boeing-717-leaking-fuel

Reminds me of a day in MD-80 flght test when ferry tanks were being tested. I looked out the right window and saw fuel streaming from the wing tip. Stuck my head in the cockpit and said " Hey guys, do you know we are dumping fuel?" Was told - "We don't have fuel dump". I says "Go back and take a look". Turned out they had run the test card wrong and overfilled the wing tanks from the ferry tanks and the rest of it was going out via the vent box.

Wonder if this incident was similar with incorrect use of transfer pumps.

EXDAC
16th Mar 2023, 01:25
Later there was a mod to permit retraction.

Closing the main gear door requires hydraulics. The Alt extension mechanically releases the main gear door and the gear which was supported by the door free falls and, hopefully, locks.

Why would alternate extension be used if there was hydraulic pressure available to close the door? A long time since I worked on MD-95 or MD-80 so may be forgetting some details.

pocker pipty
16th Mar 2023, 07:09
It’s been a while, but from memory, after an alternate extension, you had to reset the alternate extension handle to get hydraulic pressure available to close the doors.

dixi188
16th Mar 2023, 10:25
So much like the BAC 1-11. I wonder if the designers had lunch together?
With the 1-11's gear doors open there were locks to fit on the jacks to prevent them closing when you were working in the wheel well. I heard of one or two incidents when locks hadn't been fitted.

bafanguy
17th Mar 2023, 17:27
Later there was a mod to permit retraction.

Some DC9s of the late 1960s vintage had a means to close the MLG doors following emergency extension (pretty sure I'm remembering this accurately but my DC9 manual is buried in the storage locker): There was a crank below the F/Os flight kit stowage area that when turned (about a zillion times) took up slack in cables attached by clips to the circumference of the MLG doors...and pulled the doors closed.

edetroit
20th Mar 2023, 16:25
Thank you again for your knowledge guys.

I have another question. Do you know what the angle is that the reversers tilt inboard please?


https://cimg4.ibsrv.net/gimg/pprune.org-vbulletin/1024x780/0478652_16f069845f58a08820c250dd4c404616df3e0581.jpg

EXDAC
20th Mar 2023, 19:46
I have another question. Do you know what the angle is that the reversers tilt inboard please?

15 degrees on the MD-80. Don't know if the same angle was used on B-717 which had different engines and nacelles. You have a good picture so it should be easy to measure.