Page:CAB Accident Report, Continental Airlines Flight 290.pdf/10

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even zero to 47 degrees, Wlll glve a deceleratlon 1n excess of 0.86 knots per Second. However, 1f the power is suddenly reduced to flight idle from that re— quired for level fllght, wlth the flaps extended to 20 degrees, there wlll be a deceleratlon of 2.8 knots per second. If thls power reductlon 15 accomplished With 32ﬂgegrees of flaps extended, a deceleration of 3.1 knots per Second Wlll occur. The alrcraft decelerated at 1.73 knots per second. Therefore, the deceleratlon was not generated by a complete power reduction and could not have been generated soleh by flap selectlon. At the same tlme the altltude remalned nearly constant for appm imately 3,000 feet down the runway then decreased to the mlnlmum value of approxmmw tely 60 feet above the ground about 5,000 feet down the 7,000rfoot runway. The Board relleves the crew 1n1t1ated a go-around at thls tlme, but the prescribed go—around procedures were not followed. The flaps were not retracted to the 20- degree peeltlon as requlred by the fllght manual and the gear remalned extended throughout the flight down the runway. The gear may have remalned extended due to the prev1ously mentloned fallure of the hydraullc system. A normal go—around shook have 1ncluded full power, flaps retracted to 20 degrees, and landing gear retracted when a rate of cllmb was establlshed. That these procedures were not followed 1n— dlcates the crew had a problem, Whlch 1n thelr cplnlon, made 1t unsafe to land the alrcraft. Further, that problem, or an addltlonal one, requlred dev1atlons from the prescrlbed go-around procedures.

The fllght over the runway as depleted by the fllght recorder showed the alr- craft accelerated at 0.9 knots per second to 138 knots and galned approx1mately 30 feet of altltude before pltchlng over. Wlth all englnes operatlng normally, exoess thrust would have been avallable above and beyond that requlred to maintaln a steam state, unaccelerated fllght The aircraft should have been able to cllmb 960 feet per mlnute wlth the landlng gear down and flaps extended 40 degrees. Wlth 32 degra of flaps and gear down the rate of cllmb should have been 1,160 feet per mlnute. 1 Therefore, the fact that the alrcraft dld not cllmb appreclably 1nd1cates e1ther ﬂﬁ the crew dld not apply full power or there was a drag factor whlch kept the alrcraﬁ from performing normally.

From the outer marker to the fleld the alrcraft was maklng a VFR approach and the ev1dence 1ndlcates they were elgnlflcantly below the ILS gllde path untll short 1y before 1t crosSed the runway threshold. ThlS can best be descrlbed as a low, flat approach. If the crew was havlng any dlfflculty at th1s tlme they made no apparent attempt to execute a go—around. When they reached the runway threshold they were 1n a pOS1tlon to land. Even though the alrSpeed was 22 knots higher thaI prescrlbed, they were wlthln 80 feet of the ground. With no obstructlons on the runway the only reasons for the crew's fallure to land must have been e1ther an un- safe landlng gear 1nd1catlon or a mlsyudged landlng approach due to the relatlvely long, low, flat, hlgh Speed, down wand, final approach. An unsafe landlng gear 1ndlcat10n could have been the result of hydraulic leaks 1n the hlgh pressure hydraullc fllters at the p01nts where the fllter cap bolts felled. These same leah may also prov1de one reason for the crew's apparent fallure to retract the landlng gear. The cockplt landlng gear control 1nd1cated that the gear had been selected up, the nose gear was Just out of the down and locked pos1tlon, and the landlng gem looks on the left maln landing gear were sllghtly wlthdrawn from the locked peeltlm It is pOSSlble that the crew had selected the gear up but the lack of hydraullc prosaure had only removed the look from the nose gear and partially removed the 10% from the left mean landlng gear before the system felled. There 15 nothlng 1n the ev1dence to 1nd1cate that, at thls pelnt, the crew was hav1ng a pitch control probﬂ There were no erratlc maneuvers. The pllot 1ncreased hls descent angle at approx1— mately the tlme he lutercepted the gllde slope of the ILS from underneath and he