Tolefson, H B

English

NASA Technical Reports Server

SECURflTh' INFcRNA1A-rIcNJ 
	
ttFNTtAI	 Copy 
LINCLASSIFIEI! 	 / 
	
NACA	 t,çt 4 
RESEARCH MEMORANDUM 
C\sE FILE COPY 
UM]NARY RESULTS FROM GUST VELOCITY 
! / 
/ . MEASUREMENTS AT HIGH ALTITUDES 
1	 i	 /	 By H. B. 
Langley Aeronautical Laboratory 
< itJ	 I	 Langley Field, Va. 
J 1 14  WI 
'Al
 
TO A
	
flE tF ThWi1U1CY 
2 1
CLASSIFIED DOCUMENT 
This inaterai contains Information affecting the National Defense of the United States aithth the meaning 
of the espionage laws, Title 18, U.S.C., Sees. 793 and 794, the transrr.loslos or revelation wi-InC. in any 
stammer to unauthorized person In print-tIed by law. 
NATIONAL ADVISORY COMMITTEE 
FOR AERONAUTICS 
WASHINGTON 
April 1, 1952
https://ntrs.nasa.gov/search.jsp?R=19930086905 2020-06-17T13:30:06+00:00Z
NACA RN L1L12a	 UNCLASsIH 
NATIONAL ADVISORY COMMITTEE FOR AERONAUTICS
RESEARCH MEMORANDUM 
PRELIMINARY RESULTS FROM GUST VELOCITY

MEASUREMENTS AT HIGH ALTITUDES 
By H. B. Tolefson 
SUMMARY 
The first sample of high-altitude gust data obtained from routine 
operations of military airplanes has been evaluated. Time-history 
records of airspeed, altitude, and acceleration available at this time 
represent about 90,000 miles of flight at altitudes up to 46,000 feet. 
The gust velocities are presented in tabular form. 
GENERAL COMMENT 
A program for collecting data on the intensity and frequency of 
occurrence of atmospheric gusts up to altitudes of about 45,000 feet 
has been initiated by the MACA to obtain gust information for use in 
airplane and missile design. These data are being. obtained from time-
history recordings of airspeed, altitude, and acceleration made during 
routine operations of several types of military airplanes. 
In view of the interest in high-altitude gust data, the inforina-
tion obtained from the operations is summarized in table I to indicate 
the gust conditions encountered at the various altitudes. The scope of 
these data is indicated in table I by the total miles flown by the 
instrumented airplanes within altitude intervals of 5,000 feet and the 
miles of rough air encountered within each altitude interval. Rough 
air is represented herein by the portions of the record in which, the 
accelerometer trace was disturbed and contained acceleration increments 
equal to or greater than O.Og. The gust data consist of the maximum 
effective gust velocity and the number of gusts with velocities above 
a threshold of 3 feet per second encountered at each altitude. The 
gust velocities were evaluated on the basis of actual wing loading. As 
a measure of the average gust experience, the table also shows the aver-
age number of gusts (above the 3-foot-per-second threshold) encountered 
per mile of flight at each altitude. Insufficient data are available at 
this time to obtain a comparison of the gust-frequency distributions at 
the various altitudes.
1WASS1E1LJ
2	 CONFIDENTIAL	 NACA RN L1L12a 
No general conclusions are warranted from table I in view of the 
limited size of this initial sample of high-altitude gust data. There 
is an indication, however, that the maximum gust velocity- and the num-
ber of gusts encountered per mile of flight decrease with increasing 
altitude. 
Langley Aeronautical Laboratory 
National Advisory Committee for Aeronautics 
Langley Field, Va.
CONFIDENTIAL
NACA RN L51L12a	 CONFIDENTIAL 
Cl) 
1.xi 
0 
I-4
CH 
0
a) 
a)r1+' 
bD (-r\ CO C'J C'\ CO N- '0 H \0 
-s	 r1 O\ (\ CO H 0 0 H 0 0 Q)H H 0 0 0 0 0 0 0 0 P1 4-1 • • • • • • • 
ci) 0 0 
bO (I) 4-4 
c+	 0 
Eo 
.bO 
- U)-
-P 
(I) 
bO
Cl) 4-i p1 N-
— 0 C'J U C\ CO N- '0 0 0 4 -4 (\ 0 C— 0 O .-4 
CN cc H H 
1)
 
An I z
4) 
a).rl E . 0 
•H 	 C)	 ci)	 P1 H c\i m H o' ON CN N- IA F ka) C.l H H H H I 
CH 
a)U) 
bO 
•d 0 O\ H cc N- G C\ N- 00, 0 03	 -	
- '.0 cc o- 0 --7:t -4 -4 cc H (I)	 p HP '.0 -4 '0 H -4 -4 \ H 
•	 0' H H (Y\ 
a)
C'\ H -4 C\J -4 N- H c-.j N- tf\ H CO C'-J H 0 -4 N- 0 C'-J 1f\ 
bO c	 (I) CN C'J O- -4 N- -4 0 
r-l-PH .' .' •S ' ' ' 
H U) r4 — H H tc\ m c- c '0 cc H C'J H H 
0 0 0 0 0 0 0 0 0 o a 0 0 0 0 0 0 0 0 o o 0 •' 0 •' 0 .' 0 •s 0 0 0 0 0 (I) 0 1C\ 0 U\ -. 0 •s Lf 'S 0 'S )fl 'S 0- 
• A H H c'-i c'.i c' c zf - IA 
0 0 0 0 0 0 0 0 0 0 •H Cil -P -P -P -P -P -P -P -P 
H 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 
'S 0S 0 •S 0 0'S 0 0 0 0 U\ 0 tr\ S 0 VN 's 0 'S tf\ 'S0 ft tC\ H H C'J C'.J c
CONFIDENTIAL 
NACA-Langley - 4-1-52 -.350 

SECURI1V INJFDRM.TKDNJ 
cI1DEN I I A L 
ucSSFIEI 
UELASSIFJEQ 
CtD!TIAL


Preliminary results from gust velocity measurements at high altitudes

Abstract

Similar works

Full text

Available Versions

NASA Technical Reports Server