PROJECT BLUE BOOK

PROJECT 10073 RECORD CARD

1. DATE 2. LOCATION | 12, CONCLUSIONS
a Mb hae
i O Probably oon
as May 19559 Duluth, Minnesota a Posnule Balen
3. DATE-TIME GROUP 4. TYPE OF OBSERVATION
Local __ . O Ground- Visual 0 Ground-Radar le Srabelty Kiera
GMT _14/02302 0 Air Visual MMKAir-Intercapt Radar | xxPossibl y Airceaft
5. PHOTOS 6. SOURCE 2D Was Astronomical
0 Yes 0D Probably Astronomical
XU No Military bi Possibly Astronomical
7. LENGTH OF OBSERVATION 8. NUMBER OF OBJECTS | 9. COURSE ~~ 10, Other Se
S eve ent Dota for Evaluation
nknown
__4-5 minutes _————__—i|_ _—_—sone = cane
10. BRIEF SUMMARY OF SIGHTING }11. COMMENTS
} . .
wo AF pilots on A/I mission locked on See case file and evaluation
UO.

rendered this incident by WADC.,
Evaluated as dcf

ATIC FORM 329 (REV 26 SEP 52)

DISPOSITION FORM

° SECURITY CLASSIFICATION (if any)
/

FILE N@, SUBJECT
Air Intelligence LIaformation Report
TO AYCINe Ey FROM WCLGI<2 DATE A? AS 1c OMMENT NO. 1
ATIN Capt Hardin ‘LtHannen/hvt
27156/B22/P23a

le kKeference ismade to af Form 112, Subject, "UFOB," dated 17 May 1955 and orig-
inated by the Intelligence Officer, llth Fighter Interceptor Sauadron,

2. Weapons Guidance Laboratory comments on referenced report are as follows:

ae Based on the vectoring and range data contained in the report, a plot
(Ficure I) of the intercept shows that the target could nave been an aircraft of simi-
lar performance to modern jet aircraft. During the intercept the target was executing
sat turn to starboard.

be. For a portion or the targets turn to starboard, the interceptor and tar-
get were flying approximately parallel (igure I,D) at about the same velocity, with
the target at 35 degrees starboard and flying parallel to the interceptor, the target
would appear as a stationary return on tne KO's scope,

Ce It is doubtful that tne pilots indicator or the RO's scope could be used

hohe A

to accurately measuz’e tne LOOO knots reported speed of the target as it was going out
in range. The maximum opening range rate that can be observed from the range rate gap

on tae pilots indicstor is 200 knots, The fire control system specification requires

that the system snould be able to measure range rate from 1200 knots closing to 200

knots opening range rate,

ad. Another possible explanation of the reported speea of the target as it
went out in range is that the interceptors radar jumped lock, For a short period of
time and with a slight misalignment of the system, the radar could aprpeer to be locked
onto the target while actually the radar had jumped lock, Under these conditions, the
return on the scope could move in such a manner that the HO would believe that the.
return was a target.

@. The reported elevation angles of the target as it was going out in
at 1000 knots are considered to be avproximate, as only the approximate elevaticn.
- +

angles of the antenna are indicated by the position of the elevation marker at
right edge of ths RO's scope. Also, because the incicated elevation angle is measured

with respect to the interceptcr heading and not with respect te ground coordinates, 2
diving or climbing attitude of the interceptor would result in a corresponding increas

or dacrease of the elevation angle.

2 Inecls LD Dorp

1, lst Ind fr 515th Air Def das eae mA
Fn) s ~~ ihe Oiosierd, set
P Gp dtd 2lJun55 Chief, Fighter Systte§ Branca
Se ist Ind fr 602d Air Intel Weapons Guidance Lavorutory
Ser Gq(ADC) dtd lJunss w/? inele

D ey S REPLACES NMK FORM 96, {| OCT. 48, WHICH MAY BE USED 16—54801-3

WW OU. SS. GOVERNMENT PRINTING OFFICZ: 1955 0-345n8a1

Rea eek stesso

AIR TECHNICAL. INTELLIGENCE CENTER
WRIGHT-PATTERSON AIR FORCE BASE
OHIG
£5 Jun 1988
SUBJECT: (Uncl) Request for Additional Information
"A
TO: Commander f"
515th Air Defense Group s 9M, 12.
Duluth Municipal Airport

Duluth, Minnesota Bb 4 je / 4

1. Reference AF Form 112, subject: UFOB, dated 17 May 1955
and originated by the Intelligence Officer, llth Fighter Interceptor
Squadron.

2. In order to facilitate an accurate analysis of the report,
request the crew of aircraft //32525 be re-interrogated as to whether
or not the target return was intermittent or steady.

FOR THE COMMAND! #:

ia ix x
: Sf’
| i ate Og
’ ? as oe | YOCHANN...

MARY E’STORM
Ist Lt. Ts AF

Assist2 ant Achat: {0 Th nt

FIS-I (17 Mey 1955) 1st Ind 24 JUN 1955
HSADQUAPTERS, 515TH AIR DEMTINSE GRONP, Duluth ‘unicipal Airport, Duluth
-innesota

TO: Comnander, Air Technical Intelligence Center, /right-Patterson iir
Force Base, Unio

Grew of sircraft ate report that target return was steady for full
period of scope coverage

1a —* w=

Lew riert. 77 ~¢
aU. 4d ERED 75 one Jina

i ERP LY ey | 54 ie
Adjutant

ee oe —_—

edad hihi? Cl Se e + ee re eee OTL ee

B/Ttr Hq S1Sth AM GFCRU, Duluth Mun Aprt, tinn
Subj: Trans of Intel Info

ATSOP (26 Way 55) lst Ind
HEADQUARTERS, 4602D AIR TWTELLIGENCE SERVICE SQUADRCN (ADC), nt Air
Force Base, Colorasio Sprincs, Colorado

TOs Commander ATIC, ATTNs ATTA#S, Wright Patterson Air “orce Base,
Dayton, Chio

/

your information. The nature of this sichting isc such that vour
orranization is probably better eaninned to handle it,

le The inclosed preliminary UYC8 revort is transmitted for

2e This orranization chec!red with the 3rd Wea

resulting in no indication of weather phenomena at

location of sighting which might help to explain this re
5 & es Bs .

ed

TAS oMmtm Asm TART
YOR TRE CCH AN LU ina

2 Inels

n/e

reo
Adjutant

-

basteipballen 2a hy Geen bc AS aude

ee

AF FORM 112 —_ zee
APPROVED 1 JUNE 1948 oo

Tiw- a fr ac

AIR INTELLIGENCE INFORMATION REPORT

‘SUBJECT. —
iu
AREA REPORTEQON.,. ..—... + FRO = te ‘ ar aie
Ui atbeN MINNESOTA | TH PedeSe (INVELLIGE E)
DATEOFREPORT |, ., DATE.OF INFORMATION. ._ ae ly EVALUATION 72 ie ie a
(way 1955 | "lo ay 1955 | Pee
Prana by oie —_——— Tate A ee SOURCE = — - sat a atid
wii Ae RAPP 2/Lt. Asst. Intell. Ufficer| Air Crew Neport
REFER L(<. number, directive, previous report, cte., as applicable) 4 me cl ae

a S % ='. bed 0

— ——

SUMMARY: (Enter concise summary of report, Give significances in final one-senience paragraph. ~ List inclosures ot Lower left. Begin text of report on AF Form 1/8—Part 1.) ns

.
-

7.44 me ae | *. s+ Php te Vv 8 Se bok id oe 7 s - . - . e
ii accordance with AFP 20082, this report describes: in detail 4

mi * > 2 . . “ai Gat Penn ete vGld Une DLs : rer
gx an unlcentizied flying object by an aircrew of this unit. The sircrew (nilot
sad radar observer) made the observations oy radax while on a routine night
raining mission, ‘ihe inexplainable speed and uaneuvers perfor ed by the object
were considered significant enough to necessitate this report.

Aporoving Urficers: A nes , /, ‘Me Yi
ID H. HOLTAN

YH A Vy
ist Lt. USAY’,
Intelligence Office

~~

’
> _

™

DISTRIBUTION BY ORIGINATOR ia are = — —-———$—$__

“=¥8 THIS DOCUMENT CONTAINS INFORMATION AFFECTING THE NATIONAL DEFENSE OF THE UNITED STATES WITHIN THE MEANING OF THE ESPIONAGE ACT. 50 U.S.C.—
"AND 32, AS AMENDEO. ITS TRANSMISSION OR THE REVELATION OF ITS CONTENTS IN ANY MANNER TO AN UNAUTHORIZED PERSON IS PROHIBITED BY LAW.
nar ipaeeee™ “ED IN WHOLE OR IN PART, BY OTHER THAN UNITED STATES AIR FORCE AGENCIES, EXCEPT BY PERMISSION OF THE DIRECTOR OF

}

tae ee . if

'** ASSIFICATION) 16—64540-3 U. 5, GOVFamMENT PRimTiT wv “

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LBL LOO OE TI ug ——~ ~ ~

AF FORM 112—PART Il

APPROVED | JUNE 1948

FROM (Agency)

oe

(CLASSIFICATION)
AIR INTELLIGENCE INFORMATION REPORT

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(le)

POO DO LOO PO P™ KF?
: 7 . ‘
mo mow &

a) a
be 5° Gt
eet Nee” Ma’? Meee” Me? NT HN.”

(2) Description of courss:

3 (rvormat fron Ark 20082)

— +--+-+—+--e

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PAGE n OF 3 PAGES

Scr’ riptto: is

jot discernable (radar sighting)
in tt i" i

" " 1 7

~wAe 14 7
wone Ciscernabdlo

v

i i

" "

Unusual characteristics of return on scone,
is sis es Gees: 3 :

Level and ais S2TEC8 Staroogra.

30 degrees above and 60 degrees starboard.

> ~~ 28 ce ; $ fo Te a one “i 5 . ~~ Fm =f ] =~

(State nant OL Observ: ey Uv jscet Came an at 15 m2 C9» A5 acsgrees
barboard, level. ie We 2 heading 45 aegrees straight and evel, tith
SL Oidinatd whettneinl wane 24+ ere
209 knots (indicated airspeed velileving 1t was target aircraft, we

turned 45 degrees starvoard and i Leaked object on :.0's scope Porire
moved over to 2U degrees starboard at end of turn.

4 t* _-
av |] és

es |
turned port again about 30 degrees and varge 2t moved over to 35 degrees
starboard. still reading level, object then came down the scope at
about 35 oe ey (ao nore than 38 degrees ami no less than 33 degreas).
larget was down from $ miles to 6 miles at 35 degrees starboard whe:
pilot began “lying he dot. id See continusd down at 35 degrees star-
board and time-to-go circle decreased from 29 seconds to go uo & or
1O seconds. On es scope target came straight down 35 accep star—
board to 6,000 yards and stopped dead. it immediately began going out
in range faster than it case in (staying very neat to 35° aSgreee stare
board), and waat from ¢,000 yards to S miles. Elevation dot then xoved
from level to 30 degrees above. Pilot's “Ne at circle went from
apout & or ten bnGorae to adout 20 sec

onds. rom the point where the
target started going out in ranze, we (the interceptor) were in
straight and level cA heH with a constant true airsveed of about 375
knots at 26,000 feet. ie took a hard port turn when this indication
was at about 9 miles (3), desreas above) and it went off the scope at
spout 10 wiles (35 degrees anove) ustinated oe
indication was going out in range, accorc ting to scopes phy met ot a
and pilot's ond :.0's expe isnce in running interception, would be
15000 00 knots.

efe er 49 eh

4, to five simites

(3) lianner of observation;

(5) tatitudes 47 deg
Longitude: 93 4

NOTE: THIS DOCUMENT CONTAINS INFORMATION AFFECTING THE NATIONAL DEFENSE OF THE UNITED STATFS WiTiim rir sere steer

Mireelectroniec: ArG-49; Ara-54
one

F=S9D, 32525, 26,000 feet, O45 :
last heading, 375 knots, oe

ir)
<
U

. . 1 a — ”\ ly e g 2
g original heading, O50 cezrees

14/0232

ight

‘rees O7!' vworta
srees O7! Jest

o-
5

41 AND 22. AS AMENDED. ITS TRANSMISSION OR THE REVELATION ©7 " ee ive sae
iT “AY NOT BE REPRODUCED IN WHOLE OR IN PART ies ip
INTELLIGENCE, USAF.
va 4 .
= * =, ff

en

sor MUS

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-_-—

4 ‘ : ha ne _ . % PE gm
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AF FORM 112—PART Il

(CLASSIFICATION)
APPROVED 1 JUNE 1948
AIR INTELLIGENCE INFORMATION REPORT
FROM (Agency) REPORT NO,
1ith F.1.S. 3 3
; | ! — oe aeemme
(6) Observers:
(a) WA
(b) Middleton, Charles M., 1/Lt.
llth FIS, Pilot (Interceptor)
Completely reliable
Fisher, Donald Gey 2) Tits
lith FIS, fadar Observer
Completely ‘eliable
(7) Weathers
(a) 6lear
(>) Surface: 90/08
6,000: 240/16

10,000: 270/07 |
16,000: 260/20
20,000: 290/20
30,000: 300/30
50,000: 280/25
80,000: 290/08

(c) Clear
\4¥ 15 plus
(e) None

(8) No information as to any unusual activity has been received.
(9) Refer to 2d

$19) Northwest at about 50 miles there were two aircraft running interceptions.

(11) Prepared by the Assistant Intelligence Officer, 11th F.I.S.
No suggestions given as to the possible cause of the sightings.

(12) None

AS 0 hey

- EDWARD A. RAPP |
2/Lt.
Apst« Intell... Officer

NOTE: THIS DOCUMENT CONTAINS INFORMATION AFFECTING THE NATIONAL DEFENSE OF THE UNITED STATES W'T ; a
31 AND 32, ASAMENDED. ITS TRANSMISSION OR THE REVELATION OF ITS CONTENTS IN *”'Y miei as wen ares
IT MAY NOT BE REPRODUCED IN WHOLE OR IN PART, BY OTHER THAN UN!T™ R ed
INTELLIGENCE, USAF.

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