Stucked in Sao Tome - Damaged Tyre

A trip to Sao Tome which is suppose to be just a turn around, end up as a night stop. During transit check found that one of the wheel have a multiple damaged beyond maintenance manual limit. There is few cut , thread chunking cut which pass through the cut protector and exposing the carcass ply, plus there is few more circumferential cuts that makes the wheel is good enough to ground the aircraft.


If we compare the damaged with reference to tyre nomenclature diagram below, it seem that the damaged is not that serious, however with the speed involved during take-off plus the effect of pressurization in flight, we have to consult the manufacturer first before decision made to release the aircraft.

How To Change Aircraft Wheel

Ever wonder how the replacement of aircraft wheel been done? With big in size and heavy in weight, without special tools it will be imposible to be done. Here is the general description of it so that all of us have some ideas how it is done.

Depend on the organisation, in the company that currently i work with, we had a wheel change trolley where the new wheel is placed as well as the nitrogen bottle needed to charge the wheel.

Aircrat will be jacked from the axle to raised it up from the ground, then one and only nut that hold the entire wheel will be loosen and unserviceable wheel ready to be removed by sliding it out from the axle.

With the wheel dolly, which can be raised and lowered, the weight of the wheel will be supported and the wheel will be slide out from the axle, later on the new wheel be placed on the dolly and slide back to the axle.

The big nut again will be tightened and torqued to certain level to ensure proper sitting of the bearing sof the wheel, then it will loosen again and final tightening at lower torque to secure the wheel.

Take note that on B737 BBJ, the only thing that hold the wheel is this big nut on the left, however this big nut is secured by two extra bolt to prevent it getting loose during operation.

Landing Gear Shock Strut Leakage.

During all this years i'm working on B737 NG, leakage on the main and nose landing gear strut is common on all aircrafts that i've worked with either Mastar or on current fleet.






I'm sure if someone unfamiliar with this situation will thinked that the this landing gear is having a problem of leakage however it is not.






As per Boeing Maintenance Tip document, this is because of new design on new 737 landing gear, thin layer of oil presence everytime the shock strut extended and this layer plus dirts that have sticked to it has been push down by a scraper seal as the shock strut compressed.


A follow-up maintenance action have to be carry-out after few hundred hours of aircraft operation, this is to ensure sufficient amount of fluid remain in the shock strut itself.

Nose Gear Low Extension

I was in Seoul, Korea from 9 Feb to 15 Feb 07, upon arrival in Incheon Airport during my walkaround check found nose gear strut with very low extension. Only 1 inch of the chrome part visible. Since tired of long 11 hours flight from Riyadh to Seoul i decided to return back to aircraft after few days.

On 12 Feb, I've made arrangement with Korea Business Airport Service (KBAS) representative, our ground handler for me to visit the aircraft to check the aircraft condition before our departure on 15th. This is a norm in VIP service as we don't want any surprise on departure date.

Miss Son from KBAS escort me to the aircraft from the terminal, security is very tight, the airport security did not allow me to bring my camera inside. Well no problem so we headed to the aircraft.

I've requested the maintenance support personnel to be there to assist me rectify the nose landing gear low extension problem. As per the maintenance manual, we are allowed to top up the nitrogen for the strut to bring it up to the specified length as per the chart in the MM as well as at the nose wheel well left hand bulkhead.

So i top up the nitrogen for the strut and got the required extension. Walkaround check found aircraft is in good condition. Headed back to the hotel after that.. long journey... 1 hr drive... no problem because they provide me nice big hyundai limo...

Thanks to Miss Son for the picture below, she shot it with her phone and email it to me.