19.05.2016: Egypt Air Flug MS804 von Paris nach Kairo vermisst
Die weiße Kapselung enthält tatsächlich Wasser zur Kühlung (danke @ cool für den Fachbegriff "Verdampfungsenthalpie"),und @ bitboy0,der das Thema erst aufgebracht hat.
Durch das Verdampfen sollen die Innereien 60 Minuten bei 1100° überstehen.Der aufgeklebte runde Flicken auf dem zweiten Bild in Beitrag #279 stammt nicht von der Produktion,sondern wurde als Verschluss aufgeklebt nachdem beim Overhaul fehlendes Wasser aufgefüllt wurde.
Beschreibung aus dem F-800 Manual:
Crash and Fire Protection Capsule:
As shown in Figure 8, the tape transport capsule is triple protected by an inner aluminum casing, an iso–thermal protection shield, a stainless steel crash casing cover, and the exterior stainless steel dust cover. The crash casing and dust cover enable the DFR to meet a test of 20,000 lbs crush per axis, instead of the 5,000 lbs called out in TSO–C51a, and provides impact protection for 1,000 g’s for 5 ms.
The iso–thermal insulation shield maintains the inner chamber at a safe temperature when subjected to an external temperature of 1100C for 1 hour, rather than the 1/2 hour specified for Type I testing
Die Reparaturanleitung:
Repair of Thermal Pack Insulation Assembly:
The thermal pack insulation assembly, which is located on the recorder assembly (Ref. IPL, Figure 3), contains a predetermined amount of water and must be within weight specifications to effectively act as a thermal barrier. The following procedure must be followed to repair this assembly:
The following tools are required for this procedure: 1. Methylene dichloride or DuPont (Duco) household cement. 2. ABS white plastic (.040 Atlas). 3. Cereta wax No. 316C (or equivalent). 4. Funnel. 5. Scale (2–kg/5–lb capacity). 6. Soldering iron (75–100 watts).
(1) Weigh the unit. At no time should the weight of the thermal box insulation assembly be 0.1 lb or 45.4 grams less than the weight stamped on the pack.
(2) Carefully examine the unit. Minor cracks, abrasions, fractures or an opened seam may be repaired by brush application of a small quantity of methylene dichloride (Item 8, Figure 601) to the affected area
(3) Drill a 0.250–inch hole in the thermal box 3/8–inch deep. Remove any residue caused by this drilling operation and wipe box clean.
CAUTION: CARE SHOULD BE TAKEN DURING THE FOLLOWING STEP TO PREVENT WATER FROM FLOWING BETWEEN THE WAXED INNER PACK AND THE PLASTIC SHELL.
(4) Insert funnel into hole snugly. Pour into funnel the amount of water necessary to bring the box weight back up to the marked weight.
(5) After the water has been absorbed by the fibrous material, remove the funnel and wipe away excess moisture. Re–weigh the box. If additional water is required, repeat step D.
(6) Once it has been determined that the pack is within weight specifications, melt some Cereta wax (Item 9, Figure 601) with the soldering iron and fill the hole. Form this wax flush with the surface of the thermal box.
(7) Cut a 3/4–inch round piece of ABS plastic (Item 10, Figure 601) and coat one surface with methylene dichloride (Item 8, Figure 601). Position this over the wax–filled hole and press firmly to ensure intimate contact. Coat edges with additional methylene dichloride and allow to dry.
(8) Re–examine the repaired pack for integrity. Mark its actual weight on the outside and reinstall into recorder
