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OMB APPROVAL
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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
Under the Securities Exchange Act of 1934
(Amendment No. )*
Environmental Tectonics Corporation
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(Name of Issuer)
Environmental Tectonics Corporation Common Stock par value $0.10
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(Title of Class of Securities)
294092101
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(CUSIP Number)
*The remainder of this cover page shall be filled out for a reporting person's
initial filing on this form with respect to the subject class of securities, and
for any subsequent amendment containing information which would alter the
disclosures provided in a prior cover page.
The information required in the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the Securities Exchange Act of
1934 ("Act") or otherwise subject to the liabilities of that section of the Act
but shall be subject to all other provisions of the Act (however, see the
Notes).
Page 1 of 4 pages
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CUSIP NO. 294092101 13G PAGE 2 OF 4 PAGES
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NAME OF REPORTING PERSON
1 S.S. or I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
Emerald Advisers, Inc.
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CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
2 (a) [_]
(b) [_]
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SEC USE ONLY
3
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CITIZENSHIP OR PLACE OF ORGANIZATION
4
Pennsylvania
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SOLE VOTING POWER
5
NUMBER OF
215,510
SHARES -----------------------------------------------------------
SHARED VOTING POWER
BENEFICIALLY 6
OWNED BY 0
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EACH SOLE DISPOSITIVE POWER
7
REPORTING
303,030
PERSON -----------------------------------------------------------
SHARED DISPOSITIVE POWER
WITH 8
0
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AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
9
303,030
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CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
10
[_]
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PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
11
9.9%
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TYPE OF REPORTING PERSON*
12
IA
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*SEE INSTRUCTIONS BEFORE FILLING OUT!
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Page 3 of 4
Schedule 13G
Emerald Advisers, Inc.
ITEM 1.
(a) The name of the issuer is Environmental Tectonics Corporation.
(b) The address of issuer's principal executive offices is County
Line Industrial Park, 125 James Way, Southhampton,
Pennsylvania 18966.
ITEM 2.
(a) The name of the person filing is Emerald Advisers, Inc.
(b) The address of the principal office of the person filing is
1857 William Penn Way, Lancaster, Pennsylvania 17601.
(c) The state of organization is Pennsylvania.
(d) The title of class of security is common stock par value
$0.10.
(e) The CUSIP number is 294092101.
ITEM 3.
(e) The person filing is an Investment Adviser registered under
Section 203 of the Investment Advisers Act of 1940.
ITEM 4.
(a) The amount beneficially owned is 303,030 shares of common
stock.
(b) The percent of class is 9.9%.
(c)(i) The number of shares as to which Emerald Advisers, Inc. has
sole voting power is 215,510.
(c)(ii) The number of shares as to which Emerald Advisers, Inc. has
shared voting power is 0.
(c)(iii) The number of shares as to which Emerald Advisers, Inc. has
sole dispositive power is 303,030.
(c)(iv) The number of shares as to which Emerald Advisers, Inc. holds
shared dispositive power is 0.
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PAGE 4 OF 4
SCHEDULE 13G
EMERALD ADVISERS, INC.
ITEM 5.
Not applicable.
ITEM 6.
Other persons have the right to receive and/or the power to direct the
receipt of dividends from, and the proceeds from the sale of, such securities.
ITEM 7.
Not applicable.
ITEM 8.
Not applicable.
ITEM 9.
Not applicable.
ITEM 10.
By signing below I certify that, to the best of my knowledge and
belief, the securities referred to above were acquired in the ordinary course of
business and were not acquired for the purpose of and do not have the effect of
changing or influencing the control of the issuer of such securities and were
not acquired in connection with or as a participant in any transaction having
such purposes or effect.
SIGNATURE
After reasonable inquiry and to the best of my knowledge and belief, I
certify that the information set forth in this statement is true, complete and
correct.
1/21/99
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Date
/s/ Scott Rehr
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Signature
Scott L. Rehr, Senior Vice President
