Tuesday, September 11, 2012

EOSID for OEMA - MADINAH / Prince Mohammad Bin Abdulaziz international Airport

OEMA is a regional airport in the western Saudi city of Medina. Opened in 1974, it handles mostly domestic flights, although it has limited scheduled international services to regional destinations such as Cairo, Doha, Dubai, Istanbul andKuwait. and It also handles charter international flights during the Hajj season. It was named after Muhammad bin Abdul-Aziz Al Saud. Only Muslims are allowed to enter the city. This is a strictly enforced law. The Pilgrims for Hajj and Umrah can enter Saudi Arabia through this airport or through Jeddah airport only.
It is the fourth busiest airport in Saudi Arabia, handling 1,592,000 passengers in 2004, including 378,715 Hajj charter passengers. On average, it handles 20-35 flights per day, although this number triples during the Hajj season and school holidays. [www.wikipedia.org]
OEMA has two runways: 17/35 and 18/36 with a mountaineous area on northern side. According to AIP, only runway 35 has a significant obstacle on its takeoff path. It is a mountain with elevation of 2812 ft above sea level.  The Type A - Aerodrome Chart for runway 35 is shown below.


 For the purpose of this analysis we will use an Airbus A330-343 aircraft with MTOW of 233 ton. Considering the above obstacle, the RTOW resulted has an MTOW of 227.3 ton for dry runway condition with takeoff configuration of 1+F, aircon ON, anti-ice OFF, QNH 1013.25 hPa, and wind 0 kt. The 5.7 ton difference is due to an obstacle limitation as shown in the RTOW below.

Thus we need to design an EOSID to avoid this obstacle to increase the MTOW. Since the mountaineous area lies on northern side, we will design an EOSID which turns to the south and ends at ETNAM holding point. The full EOSID procedure text is "Climb STRAIGHT ahead at V2. At D3 PMA turn RIGHT with V2 and max 15 deg bank angle to heading 225 deg. Intercept R-188 PMA outbound to ETNAM and hold as required." The planview of EOSID overlays a contour chart is shown below.

We avoided the obstacle, but now we have 5 new obstacles along the turning takeoff path. It is depicted as red dot on the contour chart. These obstacles have a less gradient (ratio of height to distance) compared to the previous one. The list of new obstacles with its correction height due to turning is given below.

The new RTOW with EOSID successfully increases the MTOW to 240.4 ton. Now, the aircraft can takeoff with full load up to it's operational  MTOW as 233 ton. The final RTOW is shown below.

-o0o-