l!c N TSB AAH 12/30 C . 1

t

N A T I 0 N A L

T R A N S P 0 R T

-A T I 0 N

S A F E T Y

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p- NATIONAL TRANSPORTATION SAFETY BOARD

Washington, D. C. 20591

FILE NO. 1-0007 1 AIRCRAFT ACCIDENT REPORT /

NORTHWEST AIRLINES, INC.,

OVER THE NORTH PACIFIC OCEAN 105 NAUTICAL MILES WEST OF 150" EAST

LONGITUDE AT 36" NORTH LATITUDE APRIL 12, 1972

ADOPTED: OCTOBER 4, 1972

BOEING 747-151. N606US

E R R A T A _ - _ - - - Please make the following changes in the subject report:

I n the abs t r ac t : Item 16, l i n e 3 , delete "at r igh t" .

Item 16, l i n e 6 , change "Five" t o "Six".

Item 16, l i n e 10, change "numerous" t o "some".

In the report: Page 1 , l i ne 6 , change "Five" t o "Six".

Page 2, l i ne 3 of l a s t paragraph, change "five"

Page 3 , l ine 3 , change "five" t o "six".

N over nb

t o "six".

Page 4 , l i ne 1 of f i f t h paragraph, change "five" t o "six".

I

ler 1 7 , 1972 REPORT NUMBER: NTSB-AAR-72-27 I

AIRCRAFT INCIDENT REPORT NEAR MID AIR COLLISION

VICINITY OF FRONT ROYAL, VIRGINIA NORTHWEST AIRLINES, BOEING 7208, N736US

LOCKHEED AIRCRAFT CORPORATION, CONVAIR 240, N737Z

APRIL 26, 1972

ADOPTED: OCTOBER 26, 1972

NATIONAL TRANSPORTATION SAFETY BOAR0 Washington, 0. C. 20591

REPORT NUMBER: NTSB-AAR-72-30

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TECHNICAL REPORT STANDARD TITLE PAGE I 1 . Report No. I 2.Government Accession No. I 3.Recipient's Catalog No.

NTSB-AAR-72-30 I 4 . Title and Subtitle Near Midair Collision, Vicinity

~736US, Lockheed Aircraft Corp., Convair 240, N7372,

5.Report Date. October 26, 1972 of Front ~oyal, Virginia, Northwest Airlines Boeing 7 2 0 B ,

6.Performing Organization ^ . . nril ?A. 1472 1 7. Author(s1 8.Performing Organization

boae

Report No.

9. Performing Organization Name and Address 10.Work Unit No.

National Transportation Safety Board 11.Contract or Grant No. Bureau of Aviation Safety Washington, D. C. 20591 13.Type of Report and

Period Covered 12.Soonsoring Agency Name and Address

I .~

I Aircraft Incident Report

NATIONAL TRANSPORTATION SAFETY BOARD Washington, D. C. 20591

April 26, 1972

I 15.Supplementary Notes

This report contains Aircraft Safety Recommendations A-72-209 & 210.

16.Abstract On April 26, 1972, at 1635 eastern standard time, Northwest Airlines, Inc.,

Flight 78 took evasive action t o avoid colliding with a Lockheed Aircraft Corporation Convair 240, N7372. Flight 78 was a regularly scheduled f l igh t from Seattle, Washington, t o Du l l e s International Airport. The Convair 240 was on a V??R f l igh t plan from Bradley International Airport, Windsor Locks, Connecticut t o Dobbins A i r Force Ease, Georgia. The incident occurred 8 miles west of Front Royal, Virginia, a t approximately 8,600 feet .

aboard the Boeing 720B. Two of the cabin attendants received medical attention There were 77 passengers, a flightcrew of three, and four cabin attendants

for minor injuries. There were five passengers and a flightcrew of two aboard the Convair. There were no injuries.

of t h i s incident was the lack of visual scanning vigilance on the part of both flightcrews t o provide safe in-flight separation while operating i n VFR f l ight conditions.

The National Transportation Safety Board determines that the probable cause

T~~ recommendations have been made t o the Federal Avia,tion Administration. l7.Key Words 18.Distribution Statement

Near Midair Collision, Aircraft Incident, V iSUa l Flight Rules (VFR), Instrument Flight Rules (Im), See and Avoid.

Released t o public Unlimited distribution

I

19.Securitv Classification I 20.Security Classification 121.No. of Pages 122.Price

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(of this report) UNCLASSIFIED

(of this page) UNCLASSIFIED 15 I

NTSB Form 1765.2 (11/70) i i

TABLE OF CONTENTS

EE Synopsis . . . . . . . . . . . . . 1 Investigation . . . . . . . . . . 2 Analysis . . . . . . . . . . . . . 6 Probable Cause . . . . . . . . . . 7 Recommendations . . . . . . . . . . 10

Appendix A - Crew Information Appendix B - Advisory Circular (AC 90-59)

iii

tion relevant to the probable cause and safety message to This report contains the essential items of informa-

be derived from this accident/incident. However, f o r those having a need for more detailed information, the original factual report of the accident/incident is on file in the Washington office of the National Transportation Safety Board. Upon request, the report will be reproduced com- mercially at an average cost of 1st per page for printed matter and 85q per page for photographs, plus postage. [Minimum charge is $2.00.)

Washington, D. C. business firm which holds the current Copies of material ordered will be mailed from the

contract for commercial reproduction of the Board's public files. Billing is sent direct to the requester by that firm and includes a $2.00 user service charge by the Safety Board for special service. This charge is in addition to the cost of reproduction. No payments should be made to the National Transportation Safety Board.

Requests for reproduction should be forwarded to the:

National Transportation Safety Board Administrative Operations Division Accident Inquiries & Records Section Washington, D. C. 20591

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/--

Adopted: October 26, 1972

File No. 4-0002

NATIONAL TRANSPOKCATION SAFETY BOARD

AIRCRAFT INCIDENT REPORT WASHINGTON, D. C. 20591

NEAR MIDAIR COLLISION VICINITY OF FRONT ROYAL, VIRGINIA

MCKHEED AIRCRAFT CORPORATION, CONVAIR 240, N737Z NORTINEST AIRLINES, BOEING 720B, N736US

APRIL 26, 1972

SYNOPSIS

N736US, took evasive action to a.void colliding with a Lockheed Aircmft Corporation Convair 240, N737Z. The incident took place at approxi- mately 8,600 feet, 8 miles west of Front Royal, Virginia, at 1635 e.s.t., April 26, 1972.

Northwest Airlines scheduled passenger Flight 78, a Boeing 720B,

Two Northwest Airlines stewardesses required medical attention for minor injuries.

There was no damage to either aircraft, and they both continued to their respective scheduled destinations.

The National Transportation Safety Board determines that the probable cause of this incident was the lack of visual scanning vigi-

while operating in VFR flight conditions. lance on the part of both flightcrews to provide safe in-flight separation

The Safety Board recommends that the Federal Aviation Administration:

1. Undertake an educational program to impress on pilots that when flying on an I F R clearance in VFR conditions, separa- tion from VFR traffic is not being provided and any traffic information issued by a controller is only a supplement to visual scanning by the crew.

2. Emphasize to the Washington AIETCC the importance of com-

Advisory Circular AC 90-59, dated February 28, 1972. plying with the "keep-'em-high'' program outlined in FAA

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INVESTIGATION

at 1213 1/ f o r the second l e g of a continuing f l i g h t from Portland, Oregon, Northwest Ai r l ines Fl ight 78 (~~78) departed from Sea t t l e , Wa.shington,

t o Dulles In te rna t iona l Airport, Washington, D.C. The f l i g h t was con- ducted under Instrument Fl ight Rules (IFR), and was without incident u n t i l t h e en route descent i n Visual Fl ight Rule (VFR) conditions f o r an approach t o Dulles Airport . There were 77 passengers and a crew of seven aboard the f l i g h t .

m78 established i n i t i a l contact with Washington A i r Route Traffic Control Center (ARTCC) at 1626:30 while descending t o F l igh t Level 210. The con t ro l l e r confirmed i d e n t i f i c a t i o n of the m8 radar t a r g e t by means of the a i rc ra f t ' s transponder i d e n t i f i c a t i o n fea tu re .

A t 1630:10, NW78 was given a radar vector for t r a f f i c and was cleared t o descend t o and maintain 8,000 f e e t ?/.

"descend and cross Front Royal at and maintain e ight thousand." A t 1635, A t 1631:05, t h e clearance was amended, and the f l i g h t was cleared t o

m78 i n i t i a t e d the avoidance maneuver. A t 1636:40, the f l i g h t was cleared t o proceed d i r e c t t o the Front Royal VUR (Very High Frequency Omni- d i rec t iona l Range) and t o depart Front Royal on a heading of 120'.

t h e following sequence of transmissions: Communications between NW78 and Washington Center terminated af'ter

A t 1637:05, Washington ARTCC advised m78 t o contact hiLles Approach Control on 119.2 MHz.

A t 1637:10, m78 acknowledged t h e transmission.

A t 1637:15, m78 asked the Center i f they had any other t r a f f i c f o r "Northwest seventy-eight ."

The Center responded at 1637:18, "Northwest seventy-eight negative."

A t approximately 1635, the first o f f i ce r saw a Convair-type a i r c r a f i , at the 10 o'clock posi t ion, which appeared t o be a t t h e same a l t i t u d e and

t r o l s and executed a descending l e f t tu rn t o avoid the o ther a i r c r a f t . on a converging course. The first o f f i c e r s t a ted t h a t he seized the con-'

- 1/ A l l times used herein a r e eas tern standard, based on the 24-hour clock.

- 2/ A l l a l t i t u d e s a re mean sea l e v e l (m.s.1.) unless otherwise noted.

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According t o the Northwest Ai r l ines captain who was f l y i n g t h e a i r c r a f t at the time of the incident , the contro l column was t h r u s t hard forwa.rd and the yoke hard over t o the l e f t . He observed t h a t the first o f f i c e r was applying the control inputs and that almost simultaneously he glimpsed a two-engine, low-wing t ranspor t type a i r c r a f t passing over- head from about the 10 o'clock pos i t ion t o the 4 o'clock posi t ion . Af te r the a i r c r a f t was returned t o l e v e l f l i g h t , the capta in asked Washington Center if there was any conf l i c t ing t r a f f i c i n the a rea and they advised, "Negative."

A t 1639:48, NWfl reported the incident t o Dulles Approach Control as follows:

had a near miss r i g h t over Front Royal we were e igh t thousand "Okay, seventy-eight and we're j u s t ge t t ing col lec ted now we

and I think we might have some injured people on board, we're checking it now: we had t o take extremely evasive ac t ion t o - avoid a midair " x

inc ident . The two injured stewardesses were taken t o the h o s p i t a l and released a f t e r examination.

NW78 landed on Runway 1 Right at Dulles Airport without f u r t h e r

The Convair 240, N7372, wa.s on a VFR f l i g h t plan from Bradley In ternat ional Airport , Windsor Locks, Connecticut, t o Dobbins A i r Force Base, Georgia. The f l i g h t followed a route from Sparta, New Jersey, t o Martinsburg, West Virginia, t o Pulaski, Virginia, and t o Dobbins A i r Force Base. The Convair 240 requested and received an a l t ime te r s e t t i n g (30.15 i n . Hg) from Martinsburg Fl ight Service S ta t ion at approximately 1620. The crew s ta ted t h a t they climbed t o 8,500 f e e t p r i o r t o reaching Martinsburg and maintained t h a t a l t i t u d e for the r e s t of the f l i g h t . They were never i n radio contact with t h e Washington ARTCC, nor were they required t o be. The a i r c r a f t was equipped with a transponder, and, according t o the crew, it was operating on Code 1200 (VF'R code).

The copi lo t of the Convair 240 s t a ted t h a t when i n the v i c i n i t y of the Front Royal VOR, he was s t a r t l e d t o see a large a i r c r a f t passing below and t o the r i g h t at the approximate 3 o'clock pos i t ion and on an e a s t e r l y heading. He estimated the v e r t i c a l clearance, at the point of passing, t o have been 300 t o 400 f e e t . The Convair 240 was on a

When he first observed the o ther a i r c r a f t , the copi lo t placed h i s hands heading of approximately 230" magnetic ( M ) at the time of the inc ident .

on the contro l column but did not disengage the a.utopilot o r a l t e r the

he d i d not see the other a i rp lane . Both p i l o t s s t a ted t h a t they f l igh tpa th of h i s a i r c r a f t . The p i l o t of the Convair 240 s t a ted t h a t

immediately noted t h e i r a l t i t u d e was exact ly 8,500 f e e t .

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co l l i s ion , and the f l i g h t continued t o Dobbins A i r Force Base and landed without f u r t h e r incident .

The f ive passengers of the Conva.ir 240 were not aware of the near

Immediately p r i o r t o the time the Washington AFLPCC con t ro l l e r effected a radar handoff of NW78 t o Dulles Approach Control, ~ ~ 7 8 over- took and passed an A i r Force C-131, using c a l l s ign "Roach 49." This a i rp lane , a mi l i t a ry version of the Convair, was at 7,000 f e e t and was operating i n accordance with an IFR f l i g h t plan from Offutt A i r Force Base, Nebraska, t o Andrews A i r Force Base, Maryland. The p i l o t of Roach 49 s ta ted that he observed two a i rp lanes pass approximately 4 miles ahead of h i s a i rp lane i n the v i c i n i t y of Front Royal. Also, he estimated t h e a l t i t u d e of the two a i rp lanes t o be approximately 10,000 t o 11,000 f ee t , and s ta ted t h a t they appeared t o have 500 t o 1,000 f e e t v e r t i c a l separation.

the recorder was not removed a t Dulles p r i o r t o the next f l i g h t . The The Cockpit Voice Recorder (CVR) from W78 was not examined, as

Fl ight Data Recorder (FDR) tape was examined i n Safety Board's Washington Office.

t o 2 minutes a f t e r the inc ident . The evasive maneuver was evident by a change i n the v e r t i c a l accelera t ion (g ) . The ver t -ica l accelera t ion went

pos i t ive , t o a normal 1.00 g pos i t ive . The a l t i t u d e t r ace showed a gain from a normal 1.00 g t o 1.40 g pos i t ive , t o 0.82 g negative, t o 1.55 g

The heading t r ace turned l e f t from 107" M t o 90" M then back t o $he r i g h t , of 75 f e e t t o 8,675 f e e t m.s.l., then a descent t o 8,075 f e e t m.s.1.

past the o r i g i n a l heading.

The FDR information wa.s p lo t ted f o r the period from 3 minutes before

clouds at 25,000 f e e t with 20 miles v i s i b i l i t y . The Northwest f l ightcrew The reported weather f o r Dulles Airport at 1625 was: t h i n sca t t e red

reported, "sky conditions at the time were sca t tered clouds at about

d i t i o n a t the time of t h i s incident as VFR with v i s i b i l i t y i n excess of 10,000 f e e t and i n haze." The Convair 240 crew reported the weather con-

5 miles i n a l l d i rec t ions , even toward the sun.

N737Z. With the t e s t s e t corrected t o 8,00~ f e e t , the p i l o t ' s a l t i m e t e r On May 2, 1972, a s t a t i c system check was performed on Convair 240,

read 8,005 f e e t , and the c o p i l o t ' s a l t ime te r read 7,985 f e e t .

An inspection and leak check was made of the No. 1 and No. 2 s t a t i c and f l i g h t recorder systems on N736US. There'were no discrepancies found

checked, and were found t o be within tolerances. i n e i t h e r system, The a l t ime te r s and f l i g h t recorder were removed, bench

Para

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Progr 1972. be cc at 1C befor p i l o t decid incon

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The Washington ARTCC cont ro l le r s t a t ed that a t the time the incident occurred, he was working f i v e IFR f l i g h t s i n t he v i c i n i t y of Front Royal

He s ta ted he did not see a VFR t a r g e t i n the area . and t h a t they were a l l producing double s lash (transponder re turn) t a rge t s .

The Federal Aviation Administrat ion's (FAA) En Route A i r T ra f f i c Control Handbook 7110.9B dated Apr i l 1, 1971, ou t l ines p r i o r i t i e s as follows:

Give f irst p r i o r i t y t o separation of aircraft as required

required but do not involve separation of aircraft. Give i n t h i s manual. Give second p r i o r i t y t o services t h a t a r e

t h i r d p r i o r i t y t o addi t iona l services t o the extent possible .

"addi t ional service" i n Chapter 4, Section 11 of Handbook 7110.9B. The issuance of radar t r a f f i c information i s designated as an

Paragraph 805 of Section 11 states:

Provide addi t iona l services t o t he extent possible contingent upon your capab i l i t y t o f i t it i n t o t h e performance of higher p r i o r i t y du t i e s and on the bas i s of t he following:

a. Provision of a service is not mandatory because many f ac to r s (such as l imi t a t i ons of t he radar, volume of traffic, communications frequency congestion and your workload) could prevent you from providing it.

b. You have complete d i sc re t ion for determining i f you are ab le t o provide.or continue t o provide a service i n a p a r t i c u l a r case.

c. Your decision not t o provide o r continue t o provide a service i n a p a r t i c u l a r case i s not subject t o question and need not be made known t o t he p i l o t ( s) .

program out l ined i n FAA Advisory Circular No. AC 90-59, dated February 28, The Washington Center was not complying with the "keep-'em'high"

1972. (See Appendix B.) This program requires t h a t terminal a i rspace be configured so t h a t high-performance a i rc ra f t en t e r t he terminal area a t 10,000 feet m.s.1. and remain a t that a l t i t u d e as long as possible

p i l o t of t he Convair 240 s ta ted t h a t i n planning the f l i g h t VFR, he before beginning a descent t o 5,000 f e e t above a i r p o r t e levat ion. The

decided t o pass wel l west of the Washington a r ea i n consideration of the incoming and outgoing j e t t r a f f i c . He fu r the r s t a t ed i n par t as follows:

"Since t he current t r a f f i c cont ro l po l icy of 'keep-'em-high' i s general ly i n e f f e c t - t h i s po l icy i s t o keep a r r i v ing tu rbo je t t r a f f i c at t he highest possible a l t i t u d e as long as possible. "

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The p i l o t thought t h a t he was far enough west t o be out of danger from eastbound descending j e t s . (See Appendix B.)

Section 91-67(a) of the Federal Aviation Regulations, s t a t e s :

When weather conditions permit, regardless of whether an operation i s conducted under Instrument Fl ight Rules or

person operating an a i r c r a f t so as t o see and avoid o ther Visual Fl ight Rules, v i g i l m c e s h a l l be maintained by each

a i r c r a f t i n compliance with t h i s sect ion.

ANALYSIS

with procedures defined i n Par t 91 of the Federal Aviation Regulations. The Convair 240's cru is ing a l t i t u d e of 8,500 f e e t was i n accordance

The Northwest f l i g h t was under radar control of Washington ARTCC and had been cleared t o descend t o 8,000 f e e t m.s.1.

t o a l t i t u d e s above 5,000 f e e t . IF'R t r a f f i c which a r r i v e s from the west Mountainous ter ra in ,west of Washington, D. C., forces VFFi t r a f f i c

and i s allowed t o descend below 10,000 f e e t crea tes a c o l l i s i o n hazard between control led and uncontrolled a i r c r a f t which Advisory Circular AC 90-59 was designed t o help prevent.

The air t r a f f i c con t ro l l e r who was working NW78 a t the time of the incident was also working four other IF'R a i r c r a f t . VFFi t r a f f i c advisor ies a r e provided t o IFFi t r a f f i c subject t o the workload and discre t ion of t h e con t ro l l e r . If t h e con t ro l l e r ha.d seen the VFR t a r g e t ( t h e Convair 240), he would have given the information t o Fl ight 58, since f i v e a i r c r a f t would no t cons t i tu te a s u f f i c i e n t l y heavy workload t o prohibi t the issuance

t r a t e d a rea may have prevented the con t ro l l e r from seeing the VFR t a r g e t of a t r a f f i c advisory. However, the f i v e beacon t a r g e t s i n a concen-

operating i n the same-area.

National Weather Service at Dulles Airport a t 1625), each a i r c r a f t could Assuming a m a x i m u m i n- f l i g h t v i s i b i l i t y of 20 miles (reported by the

have been v i s i b l e t o the o ther f o r approximately 3 minutes and 20 seconds p r i o r t o the near co l l i s ion . A t the approximate closure angle of 125O, the Convair would have remained at the approximate 11 o'clock pos i t ion r e l a t i v e t o NW78, and W7'8 would have been at the approximate 1 o'clock pos i t ion and s l i g h t l y above the Convair throughout t h i s time period.

Thus, it is t h e opinion of the Board t h a t t h i s time frame, as well as t h e r e l a t i v e pos i t ion of each a i r c r a f t t o the other, should have provided ample opportunity f o r each crew t o have observed the other air- c r a f t and t o have taken correc t ive ac t ion wel l before the near c o l l i s i o n occurred.

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The "see and avoid" concept remains a primary doctrine for collision avoidance between aircraft operating in visual meteorological conditions. Operational conditions such as high closing speeds and physiological inhibitors to visual detection, which would have limited the ability to

Vigilance must be maintained by flightcrews to see and avoid other air- see and avoid the other aircraft, were not factors in this incident.

rules or visual flight rules. ATC radar advisory service, where available, craft whether the operation is being conducted under instrument flight

is intended as a supplement to the required pilot vigilance.

PROBABLE CAUSE

The National Transportation Safety Board determines that the prob- able cause of this incident was the lack of visual scanning vigilance

while operating in VFR flight conditions. on the part of both flightcrews to provide safe in-flight separation

RECOMMENJNTIONS

The Safety Board recommends that the Federal Aviation Administration:

1. Undertake an educational program to impress on pilots that when flying on an IFR clearance in VFR conditions, separa- tion from VFR traffic is not being provided and any traffic information issued by a controller is only a supplement to visual scanning by the crew. (A-72-209)

2. Emphasize to the Washington AIETCC the importance of complying with the "keep-'em-high" program outlined in FAA Advisory Circular, AC 90-59, dated February 28, 1972. (A-72-210)

BY THE NATIONAL TRANSPORTATION SAFETY BOARD

/s/ J O H N H. REED Chairman

/ s / FRANCIS H. McAWS Member

/s/ ISABEL A. BURGESS Member

/ s / WILLIAM R. HALEY Member

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AFTENDM A

CREW INFORMllTION

A. Boeing 720B, N736US

Transport Pilot Certificate No. 437248. His first-class medical certifi- cate was dated April 1, 1972. His total flying time was 15,618 hours, 5,738 hours of which were in the Boeing 720.

The pilot-in-command, Captain Robert L. Scott, aged 44, held Airline

First Officer Richard Drzal, aged 28, held Airline Transport Pilot

May 10, 1971. His flying time was 2,908 hours, 1,200 hours of which were Certificate No. 1621943. His first-class medical certificate was dated

in the Boeing 720.

B. Convair 240, N737Z

Pilot Carl P. Setili, aged 54, held Airline Transport Pilot Certifi- cate No. 33591-40. His first-class medical certificate, dated December 16, 1971, contained the following limitation: “Holder shall possess correct- ing glasses for near and distant vision while exercising the privilege of his airman’s certificate.” He had accumulated 10,140 hours flying time, as shown on the a,pplication for his medical certificate.

Copilot Raleigh E. Drennon, aged 37, held Airline Transport Pilot Certificate No. 1346291. His first-class medical certificate was dated June 7, 1971. The application for his medical certificate shows 2,200 hours of civilian flying time a.nd 3,300 hours of military flying time.

.

- 9 - AC NO: AC 90- 59 APPENDIX B

DEPARTMEDIT OF TRANSPORTATION FEDERAL AVIATION ADMINISTRATION SUBJECT- ARRIVAL AND DEPARTURE HANDLING

* OF HIGH PERFORMANCE AIRCRAFT

1. PURPOSE. This Advisory Circular describes A n : handling of high performance a i r c r a f t i n terminal areas. It i s designed t o fami l ia r ize

of t h e program may be realized. p i lo t s w i t h the keep-'em-high procedures so t h a t t o t a l effect iveness

2. RELATED DOCUMENTS.

a. Airman's Information Manual, Par t s I and IV. b. FAA Order 7110.22A, Arrival and Departure Handling of High

Performance Aircraf t .

3. DISCUSSION.

a. The FAA Near Mida i r Coll is ion Report of 1968 revealed t h a t a high percentage of terminal near midair co l l i s ions occur below 8,000 f e e t within 30 miles of an a i rpo r t with a control tower. The most c r i t i c a l area of t h i s a irspace i s a t the lower a l t i t u d e s which a r e extensively used by controlled and uncontrolled a i r c ra f t .

FAA developed a program which i s designed to minimize exposure of I n an e f f o r t t o reduce the number of inc idents of t h i s nature, the

controlled a r r iv ing and departing high performance a i r c r a f t i n the terminal area. It i s commonly referred to a s t he "Keep-'em-High"

and they have proven to be an e f f ec t ive noise abatement program program. The procedures have been i n e f f e c t fo r about one year

i n addi t ion to reducing the time t h a t high performance a i r c r a f t are exposed t o uncontrolled a i r c r a f t a t lower a l t i tudes .

AC 90-59 - 10 - 28 Feb 72

4.

5 .

b. The keep-'em-high program requires terminal a irspace be configured so t ha t high performance a i r c r a f t enter the terminal area a t 10,000

descent to 5,000 f e e t above a i r p o r t elevation. Descent below the f e e t and remain a t t h a t a l t i t u d e a s long as possible before beginning

5,000 foot a l t i t u d e begins when the a r r i v a l en ters the descent area established f o r the landing direct ion. Departing a i r c r a f t a r e climbed to the highest a l t i t u d e f i l e d by the p i l o t as soon as

will not i n i t i a t e clearances t o a r r iv ing and departing high possible a f t e r takeoff. In keeping with t h i s program, cont ro l le rs

performance a i r c r a f t which will place them a t lower a l t i t u d e s commonly

below 5,000 f e e t above a i r p o r t elevation w i l l not be honored u n t i l the used by uncontrolled a i r c r a f t . Routine p i l o t requests f o r a l t i t u d e s

a i r c r a f t has entered the descent area establ ished f o r the landing runway. A t non-radar approach control f a c i l i t i e s exceptions a r e made t o provide the cont ro l le r f l e x i b i l i t y i n accommodating lower a l t i t u d e requests within spec i f ic parameters.

c. To a s s i s t VFR p i lo t s , FAA f a c i l i t y chiefs will normally issue F a c i l i t y Bullet ins explaining the program and describing loca l

descent areas and normal a r r i v a l and departure routes. These procedures. It will be accompanied by a graphic not ice depict ing

char t s a r e designed to help VFR p i l o t s to i den t i fy areas and

Avoiding these a reas will r e s u l t i n a higher degree of sa fe ty routes t h a t are normally used by high performance a i r c r a f t .

i n the terminal area.

APPLICABILITY. As used i n t h i s program, high performance a i r c r a f t means turboje ts and large turboprops that f i l e IPR a t 5,000 f e e t AGL or above. I n mst cases the formal f a c i l i t y b u l l e t i n w i l l be issued. A t the lower densi ty locat ions the keep-'em-high procedures w i l l be applied by cont ro l le rs without a formal advert is ing program. Since

f o r a i r p o r t neighbors, they will be applied a t a l l times by a i r these procedures a r e designed f o r safe ty enhancement and noise relief

due to unusual circumsfances, e.g., turbulent conditions, thunder- t r a f f i c cont ro l le rs except when d i f f e ren t a l t i t u d e s a r e necessary

storm a c t i v i t y , loca l noise abatement requirements, aircraft emergencies, etc.

MISCELLANEOUS. The FAA bel ieves t h i s program enhances safe ty and af fords s igni f icant noise r e l i e f t o our a i r p o r t neighbors. P i l o t s of high

Tra f f i c Control. When p i l o t s of these par t icu lar a i r c r a f t a r e f ly ing performance a i r c r a f t , when f ly ing I P R , are urged t o cooperate with Air

VFR they a r e encouraged t o abide by the keep-'em-high philosophy, i.e.3

Page 2 Par 3

I

6

3

- AC 90-59 - 11 - 28 Feb 72

4.

5 .

b. The keep-'em-high program requires terminal a i r space be configured

f e e t and remain a t t h a t a l t i t u d e a s long a s possible before beginning so t h a t high performance a i r c r a f t enter the terminal area a t 10,000

descent to 5,000 f e e t above a i rpo r t elevation. Descent below the 5,000 foot a l t i t u d e begins when the a r r i v a l en ters the descent area established f o r the landing direction. Departing a i r c r a f t are climbed to the highest a l t i t u d e f i l e d by the p i l o t as soon a s possible afte.r takeoff. In keeping with t h i s program, cont ro l le rs will not i n i t i a t e clearances t o a r r iv ing and departing high performance a i r c r a f t vhich will place them a t lower a l t i t u d e s commonly

below 5,000 f e e t above a i r p o r t e levat ion will not be honored u n t i l the used by uncontrolled a i r c r a f t . Routine p i l o t requests f o r a l t i t u d e s

a i r c r a f t has entered the descent area establ ished f o r the landing runway. A t non-radar approach control f a c i l i t i e s exceptions a r e made t o provide the cont ro l le r f l e x i b i l i t y i n accommodating lower a l t i t u d e requests within spec i f ic parameters.

C. To assist VFR p i l o t s , FAA f a c i l i t y chiefs w i l l normally issue F a c i l i t y Bullet ins explaining the program and describing loca l procedures. It w i l l be accompanied by a graphic not ice depict ing descent areas and normal a r r i v a l and departure routes. These char t s a r e designed t o help VFR p i l o t s to ident i fy a reas and

Avoiding these a reas will r e s u l t i n a higher degree of s a fe ty routes t ha t a r e normally used by high performance a i r c r a f t .

i n the terminal area.

ApPLICABILITY. As used i n t h i s program, high performance a i r c r a f t means turboje ts and large turboprops that f i l e IFR a t 5,000 f e e t AGL

A t the lower density locat ions the keep-'em-high procedures will be or above. I n mst cases the formal f a c i l i t y b u l l e t i n will be issued.

applied by cont ro l le rs without a formal advert is ing program. Since

f o r a i r p o r t neighbors, they will be applied a t a l l times by a i r these procedures a r e designed fo r safe ty enhancement and noise relief

due to unusual circumstances, e.g., turbulent conditions, thunder- t r a f f i c cont ro l le rs except when d i f f e ren t a l t i t u d e s a r e necessary

storm a c t i v i t y , loca l noise abatement requirements, a i r c r a f t emergencies, etc.

MISCELLANEOUS. The FAA believes t h i s program enhances safe ty and af fords s igni f icant noise r e l i e f t o our a i rpo r t neighbors. P i l o t s of high

Traf f ic Control. When p i l o t s of these par t icu lar a i r c r a f t a r e f ly ing performance a i r c r a f t , when f ly ing IFR, are urged t o cooperate w i t h A i r

VFR they a r e encouraged to abide by t h e keep-'em-high philosophy, i.e.,

Page 2 par 3

28 Feb 72 - 12 - AC 90-59

a i r c r a f t a r e urged to avoid, to the extent possible, the routes and remain as high a s possible as long as possible. P i l o t s of o ther VFR

descent areas mst frequently used by high performance a i r c r a f t i n the terminal area. When these areas must be traversed, extreme vigilance should be exercised by VFR pi lo ts . Although con t ro l le r s will abide by the established keep-'em-high procedures mSt of the time, there a r e times, as mentioned ea r l i e r , when deviations w i l l be required.

dL&A!L c*l lf

NTSB Near Midair Col l is ion AAR 72-30 Virginia

Yisinity of Front ROY&

WILLIAM M. PLENER Director, Air Traf f ic Service

NTSB Near Midair Col l is ion AAR v i c i n i t y of Front Royal 72-30. . Virginia. I c. 1