------------------------------------

                         ARIZONA PUBLIC SERVICE COMPANY

                                       TO

                              THE BANK OF NEW YORK

                                     Trustee

                              ---------------------

                          Second Supplemental Indenture

                            Dated as of April 1, 1997

                                       To

                                    Indenture

                          Dated as of November 15, 1996

                              ---------------------


                           6.72% Senior Notes Due 1999

                      ------------------------------------


         SECOND  SUPPLEMENTAL  INDENTURE,  dated as of April  1,  1997,  between
Arizona Public Service Company,  a corporation duly organized and existing under
the laws of the State of  Arizona  (herein  called  the  "Company"),  having its
principal office at 400 North Fifth Street, Phoenix, Arizona 85004, and The Bank
of New York,  a New York  banking  corporation,  as Trustee  (herein  called the
"Trustee") under the Indenture dated as of November 15, 1996 between the Company
and the Trustee (the "Indenture").

                             RECITALS OF THE COMPANY

         The Company has executed and  delivered the Indenture to the Trustee to
provide for the issuance  from time to time of its Senior  Notes (the  "Notes"),
said Notes to be issued in one or more series as in the Indenture provided.

         The Company has  executed and  delivered  to the Trustee one  indenture
supplemental to the Indenture (the "First  Supplemental  Indenture") dated as of
November 15, 1996.

         Pursuant to the terms of the Indenture,  the Company desires to provide
for the  establishment  of a new  series  of its  Notes to be known as its 6.72%
Senior Notes Due 1999 (herein called the "Senior Notes Due 1999"),  the form and
substance  of such  Senior  Notes  Due  1999  and  the  terms,  provisions,  and
conditions  thereof to be set forth as provided in the Indenture and this Second
Supplemental Indenture.

         All things necessary to make this Second Supplemental Indenture a valid
agreement of the Company,  and to make the Senior Notes Due 1999,  when executed
by the  Company  and  authenticated  and  delivered  by the  Trustee,  the valid
obligations of the Company, have been done.

         NOW, THEREFORE, THIS SECOND SUPPLEMENTAL INDENTURE WITNESSETH:

         For and in consideration of the premises and the purchase of the Senior
Notes Due 1999 by the Holders thereof,  and for the purpose of setting forth, as
provided in the  Indenture,  the form and substance of the Senior Notes Due 1999
and the terms,  provisions,  and conditions  thereof, it is mutually agreed, for
the equal and proportionate benefit of all Holders of the Senior Notes Due 1999,
as follows:

                                   ARTICLE ONE

                         GENERAL TERMS AND CONDITIONS OF
                            THE SENIOR NOTES DUE 1999

         SECTION 101. There shall be and is hereby  authorized a series of Notes
designated  the "6.72%  Senior Notes Due 1999,"  limited in aggregate  principal
amount to  $50,000,000,  which amount shall be as set forth in any Company Order
for the  authentication  and delivery of Senior Notes Due 1999. The Senior Notes
Due 1999 shall mature and the principal  shall be due and payable  together with
all accrued and unpaid interest thereon on April 1, 1999, and shall be issued in
the form of registered Senior Notes Due 1999 without coupons.

         SECTION 102. The Senior Notes Due 1999 shall be issued in  certificated
form,  except  that the  Senior  Notes Due 1999 shall be issued  initially  as a
Global  Note to and  registered  in the name of Cede & Co.,  as  nominee  of The
Depository Trust Company, as Depositary  therefor.  Any Senior Notes Due 1999 to
be issued or  transferred  to, or to be held by,  Cede & Co.  (or any  successor
thereof) for such purpose shall bear the depositary  legend in substantially the
form set forth at the top of the form of  Senior  Note Due 1999 in  Article  III
hereof  (in lieu of that set  forth in  Section  204 of the  Indenture),  unless
otherwise  agreed by the Company,  such  agreement to be confirmed in writing to
the  Trustee.  Such Global Note may be  exchanged in whole or in part for Senior
Notes Due 1999  registered,  and any transfer of such Global Note in whole or in
part  may be  registered,  in the  name or  names of  Persons  other  than  such
Depositary or a nominee thereof only under the circumstances set forth in Clause
(2) of the  last  paragraph  of  Section  305 of the  Indenture,  or such  other
circumstances  in addition to or in lieu of those set forth in Clause (2) of the
last  paragraph of Section 305 of the  Indenture  as to which the Company  shall
agree,  such agreement to be confirmed in writing to the Trustee.  Principal of,
and premium,  if any, and interest on the Senior Notes Due 1999 will be payable,
the transfer of Senior Notes Due 1999 will be  registrable  and Senior Notes Due
1999 will be exchangeable for Senior Notes Due 1999 bearing  identical terms and
provisions,  at the office or agency of the Company in the Borough of Manhattan,
The City and State of New York; provided,  however, that payment of interest may
be made at the option of the Company by check mailed to the registered holder at
such address as shall appear in the Security Register.

         SECTION 103.  Each Senior Note Due 1999 will bear  interest at the rate
of 6.72% per annum from April 10, 1997 until the principal  thereof  becomes due
and  payable,  and on any overdue  principal  and (to the extent that payment of
such interest is enforceable under applicable law) on any overdue installment of
interest  at the same rate per annum,  payable on April 1 and  October 1 of each
year (each, an "Interest  Payment Date"),  commencing on October 1, 1997, to the
person in whose name such  Senior Note Due 1999 or any  predecessor  Senior Note
Due 1999 is registered, at the close of business on the March 15 or September 15
next preceding such Interest Payment Date; provided,  however, that the interest
payable at  maturity  will be payable to the person to whom  principal  shall be
payable.  Any such interest installment not punctually paid or duly provided for
shall  forthwith  cease to be payable to the registered  holders on such regular
record  date,  and may be paid to the person in whose  name the Senior  Note Due
1999 (or one or more  Predecessor  Notes) is registered at the close of business
on a special  record  date to be fixed by the  Trustee  for the  payment of such
defaulted  interest,  notice whereof shall be given to the registered holders of
the  Senior  Notes Due 1999 not less than 10 days prior to such  special  record
date,  or may be paid at any time in any other  lawful  manner not  inconsistent
with the  requirements of any securities  exchange on which the Senior Notes Due
1999 may be listed,  and upon such notice as may be  required by such  exchange,
all as more fully provided in the Indenture.

         The amount of  interest  payable for any period will be computed on the
basis of a 360-day year of twelve 30-day months. Interest will accrue from April
10, 1997 to, but not including, the relevant payment date. In the event that any
date on which interest is payable on the Senior Notes Due 1999 is not a Business
Day,  then  payment  of  interest  payable on such date will be made on the next
succeeding  day which is a  Business  Day (and  without  any  interest  or other
payment in respect of any
                                        2

such  delay),  except  that,  if such  Business  Day is in the  next  succeeding
calendar year, such payment shall be made on the immediately  preceding Business
Day,  in each case with the same  force and  effect as if made on such  date.  A
"Business Day" shall mean any day other than a day on which banking institutions
in The City of New York are authorized or obligated by law to close.

         SECTION 104. The Company,  at its option, may redeem all, or, from time
to time,  any part of the Senior Notes Due 1999,  upon notice as provided in the
Indenture at a redemption  price equal to the sum of (a) the principal amount of
the Senior  Notes Due 1999 (or portion  thereof)  being  redeemed  plus  accrued
interest  thereon to the redemption date and (b) the Make-Whole  Amount (if any)
with respect to the Senior Notes Due 1999 or portion thereof being redeemed.

         For purposes of this Section  104, the  following  terms shall have the
following meanings:

         "Make-Whole Amount" means in connection with any optional redemption of
any Senior  Notes Due 1999,  the excess,  if any, of (i) the  aggregate  present
value  as of the date of such  redemption  of each  dollar  of  principal  being
redeemed and the amount of interest  (exclusive of interest  accrued to the date
of  redemption)  that would have been  payable in respect of each such dollar if
such redemption had not been made  determined by  discounting,  on a semi-annual
basis,  such principal and interest at the Reinvestment  Rate (determined on the
third  Business Day  preceding the date such notice of redemption is given) from
the  respective  dates on which  such  principal  and  interest  would have been
payable, if such redemption had not been made, over (ii) the aggregate principal
amount of the Senior Notes Due 1999 being redeemed.

         "Reinvestment  Rate" means 0.10% plus the arithmetic mean of the yields
under  the  respective  heading  "Week  Ending"  published  in the  most  recent
Statistical  Release under the caption  "Treasury  Constant  Maturities" for the
maturity  (rounded to the nearest month)  corresponding to the remaining life to
maturity, as of the payment date of the principal being redeemed. If no maturity
exactly  corresponds to such maturity,  yields for the two published  maturities
most closely  corresponding to such maturity shall be calculated pursuant to the
immediately  preceding  sentence and the Reinvestment Rate shall be interpolated
or extrapolated from such yields on a straight-line  basis,  rounding in each of
such relevant  periods to the nearest month.  For the purpose of calculating the
Reinvestment  Rate, the most recent  Statistical  Release published prior to the
date of determination of the Make-Whole Amount shall be used.

         "Statistical   Release"  means  the  statistical   release   designated
"H.15(519)"  or any  successor  publication  which is  published  weekly  by the
Federal  Reserve System and which  establishes  yields on actively traded United
States  government  securities  adjusted  to  constant  maturities,  or, if such
statistical  release is not published at the time of any determination under the
Indenture, then such other reasonably comparable index which shall be designated
by the Company.

         The Trustee  shall be under no duty to inquire into,  may  conclusively
presume  the  correctness  of, and shall be fully  protected  in acting upon the
Company's  calculation of any redemption price,  including any Make-Whole Amount
(if any).
                                        3

         SECTION 105. The related series of Senior Note First Mortgage Bonds for
the Senior Notes Due 1999 is the Company's  First Mortgage  Bonds,  Senior Notes
Series B (the "Senior Note Series B Bonds").

         SECTION 106.  When the  obligation of the Company to make payments with
respect to the  principal  of, and  premium,  if any, and interest on all or any
part of the Senior Note Series B Bonds shall be  satisfied  or deemed  satisfied
pursuant to Section 403, Section 501, or Article 14 of the Indenture or pursuant
to Section 104 of this Second  Supplemental  Indenture,  the Trustee shall, upon
written  request of the Company and the receipt of the certificate of the Expert
described  in  Section  404(b) of the  Indenture  (if such  certificate  is then
required by Section  404(b) of the  Indenture),  deliver to the Company  without
charge  therefor  all of the Senior Note Series B Bonds so  satisfied  or deemed
satisfied,  together with such appropriate instruments of transfer or release as
may be  reasonably  requested  by the  Company.  All Senior  Note Series B Bonds
delivered to the Company in accordance  with this Section 106 shall be delivered
by the Company to the First Mortgage Trustee for cancellation.

         SECTION 107. The Senior Notes Due 1999 shall be defeasable  pursuant to
Section 1402 and Section 1403 of the Indenture.

                                   ARTICLE TWO

                              ADDITIONAL COVENANTS

         SECTION  201.  (a) From and after the  Release  Date and so long as any
Senior Notes Due 1999 are Outstanding,  the Company will not issue,  assume,  or
guarantee any Debt secured by any mortgage,  security interest,  pledge, or lien
(herein  referred to as a "mortgage")  of or upon any Operating  Property of the
Company,  whether owned at the date of the Indenture or thereafter acquired, and
will not  permit  to exist  any Debt  secured  by a  mortgage  on any  Operating
Property  created  on or prior to the  Release  Date,  without  in any such case
effectively  securing,  on the later to occur of the  issuance,  assumption,  or
guarantee of any such Debt or the Release Date, the Outstanding Senior Notes Due
1999 (together  with, if the Company shall so determine,  any other Note or Debt
of or guaranteed by the Company  ranking  senior to, or equally with, the Notes)
equally  and  ratably  with such Debt;  provided,  however,  that the  foregoing
restriction shall not apply to Debt secured by any of the following:

                           (1)      mortgages  on any  property  existing at the
                                    time of acquisition thereof;

                           (2)      mortgages  on  property  of  a   corporation
                                    existing  at the time  such  corporation  is
                                    merged   into  or   consolidated   with  the
                                    Company, or at the time of a sale, lease, or
                                    other  disposition of the properties of such
                                    corporation  or a  division  thereof  as  an
                                    entirety or  substantially as an entirety to
                                    the Company,  provided that such mortgage as
                                    a
                                        4

                                    result of such merger, consolidation,  sale,
                                    lease, or other  disposition is not extended
                                    to property owned by the Company immediately
                                    prior thereto;

                           (3)      mortgages  on property to secure all or part
                                    of  the  cost  of  acquiring,  constructing,
                                    developing,   or  substantially   repairing,
                                    altering,  or improving such property, or to
                                    secure  indebtedness   incurred  to  provide
                                    funds   for   any   such   purpose   or  for
                                    reimbursement of funds  previously  expended
                                    for  any   such   purpose,   provided   such
                                    mortgages    are    created    or    assumed
                                    contemporaneously  with, or within  eighteen
                                    (18)  months  after,   such  acquisition  or
                                    completion of construction,  development, or
                                    substantial    repair,     alteration,    or
                                    improvement   or  within   six  (6)   months
                                    thereafter  pursuant  to  a  commitment  for
                                    financing arranged with a lender or investor
                                    within such eighteen (18) month period;

                           (4)      mortgages  in favor of the United  States of
                                    America  or  any  State   thereof,   or  any
                                    department,  agency, or  instrumentality  or
                                    political  subdivision  of the United States
                                    of America or any State thereof,  or for the
                                    benefit of holders of  securities  issued by
                                    any such entity, to secure any Debt incurred
                                    for the purpose of financing all or any part
                                    of  the  purchase   price  or  the  cost  of
                                    constructing,  developing,  or substantially
                                    repairing,   altering,   or  improving   the
                                    property subject to such mortgages; or

                           (5)      any extension,  renewal or  replacement  (or
                                    successive    extensions,    renewals,    or
                                    replacements),  in whole or in part,  of any
                                    mortgage   referred  to  in  the   foregoing
                                    clauses  (1) to  (4),  inclusive;  provided,
                                    however,  that the principal  amount of Debt
                                    secured thereby and not otherwise authorized
                                    by said clauses (1) to (4), inclusive, shall
                                    not  exceed  the  principal  amount of Debt,
                                    plus  any   premium   or  fee   payable   in
                                    connection with any such extension, renewal,
                                    or  replacement,  so  secured at the time of
                                    such extension, renewal, or replacement.

                                    (b)   Notwithstanding   the   provisions  of
Section 201(a),  from and after the Release Date and so long as any Senior Notes
Due 1999 are Outstanding,  the Company may issue,  assume, or guarantee Debt, or
permit to exist Debt,  secured by mortgages  which would otherwise be subject to
the  restrictions  of Section 201(a) up to an aggregate  principal  amount that,
together with the principal  amount of all other Debt of the Company  secured by
mortgages (other than mortgages permitted by Section 201(a) that would otherwise
be  subject  to the  foregoing  restrictions)  and the  Value  of all  Sale  and
Lease-Back  Transactions  in  existence  at such time  (other  than any Sale and
Lease-Back Transaction that, if such Sale and Lease-Back Transaction had been
                                        5


a mortgage,  would have been  permitted by Section  201(a),  other than Sale and
Lease-Back Transactions permitted by Section 202 because the commitment by or on
behalf of the  purchaser  was obtained no later than  eighteen (18) months after
the later of events described in (i) or (ii) of Section 202, and other than Sale
and Lease-Back Transactions as to which application of amounts have been made in
accordance  with  clause (z) of Section  202),  does not at the time  exceed the
greater of ten percent  (10%) of Net  Tangible  Assets or ten  percent  (10%) of
Capitalization.

                                    (c) If at any time the Company  shall issue,
assume,  or guarantee  any Debt  secured by any  mortgage and if Section  201(a)
requires  that the  Outstanding  Senior  Notes Due 1999 be secured  equally  and
ratably with such Debt, the Company will promptly execute,  at its expense,  any
instruments  necessary to so equally and ratably secure the  Outstanding  Senior
Notes Due 1999 and deliver the same to the Trustee along with:

                           (1)      An  Officers'  Certificate  stating that the
                                    covenant of the Company contained in Section
                                    201(a) has been complied with; and

                           (2)      An Opinion of Counsel to the effect that the
                                    Company  has  complied   with  the  covenant
                                    contained  in Section  201(a),  and that any
                                    instrument  executed  by the  Company in the
                                    performance  of such covenant  complies with
                                    the requirements of such covenant.

                  In  the  event  that  the  Company  shall   hereafter   secure
Outstanding  Senior Notes Due 1999 equally and ratably with any other obligation
or  indebtedness  (including  other Notes)  pursuant to the  provisions  of this
Section  201,  the Trustee is hereby  authorized  to enter into an  indenture or
agreement supplemental hereto and to take such action, if any, as it may, in its
sole and absolute discretion, deem advisable to enable it to enforce effectively
the  rights of the  Holders of  Outstanding  Senior  Notes Due 1999 so  secured,
equally and ratably with such other obligation or indebtedness.

         SECTION 202.  From and after the Release Date and so long as any Senior
Notes Due 1999 are  outstanding,  the  Company  will not enter into any Sale and
Lease-Back  Transaction  with  respect to any  Operating  Property  and will not
permit to remain in effect any Sale and Lease-Back  Transaction  entered into on
or prior to the Release Date with respect to any  Operating  Property if, in any
case,  the  commitment  by or on behalf of the purchaser is or was obtained more
than  eighteen  (18)  months  after  the  later  of (i)  the  completion  of the
acquisition, construction, or development of such Operating Property or (ii) the
placing in operation of such Operating Property or of such Operating Property as
constructed,  developed, or substantially repaired, altered, or improved, unless
(x) the Company would be entitled  pursuant to Section 201(a) to issue,  assume,
or  guarantee  Debt  secured by a mortgage on such  Operating  Property  without
equally and ratably  securing the Senior Notes Due 1999 or (y) the Company would
be entitled  pursuant to Section  201(b),  after giving  effect to such Sale and
Lease-Back  Transaction,  to incur $1.00 of additional Debt secured by mortgages
(other than  mortgages  permitted  by Section  201(a)) or (z) the Company  shall
apply or cause to be applied, in the case of a sale or transfer for cash,
                                        6

an amount equal to the net  proceeds  thereof (but not in excess of the net book
value of such  Operating  Property at the date of such sale or transfer) and, in
the case of a sale or transfer  otherwise  than for cash, an amount equal to the
fair value (as  determined by the Board of Directors) of the Operating  Property
so leased,  to the  retirement,  within one hundred  eighty (180) days after the
later to occur of the effective date of such Sale and Lease-Back  Transaction or
the Release  Date, of Notes or other Debt of the Company  ranking  senior to, or
equally  with,  the  Senior  Notes Due 1999;  provided,  however,  that any such
retirement of Notes shall be in accordance  with the terms and provisions of the
Indenture  and the Notes;  provided,  further,  that the amount to be applied to
such  retirement  of Notes or other Debt shall be reduced by an amount  equal to
the sum of (a) an amount  equal to the  redemption  price with  respect to Notes
delivered  within such one hundred  eighty  (180)-day  period to the Trustee for
retirement and  cancellation and (b) the principal  amount,  plus any premium or
fee paid in connection with any redemption in accordance with the terms of other
Debt voluntarily retired by the Company within such one hundred eighty (180)-day
period, excluding in each case retirements pursuant to mandatory sinking fund or
prepayment provisions and payments at maturity.

         SECTION 203. Definitions

         For purposes of Section 201 and Section 202 of this Second Supplemental
Indenture, the following terms shall have the following meanings:

         "Capitalization"  means the total of all the following  items appearing
on,  or  included  in,  the  consolidated  balance  sheet  of the  Company:  (i)
liabilities for indebtedness maturing more than twelve (12) months from the date
of  determination;  and (ii) common stock,  preferred stock,  premium on capital
stock,  capital surplus,  capital in excess of par value, and retained  earnings
(however the  foregoing  may be  designated),  less, to the extent not otherwise
deducted,  the  cost of  shares  of  capital  stock of the  Company  held in its
treasury.

         Subject  to  the  foregoing,  Capitalization  shall  be  determined  in
accordance  with  generally   accepted   accounting   principles  and  practices
applicable  to the type of business in which the Company is engaged and that are
approved by independent  accountants  regularly retained by the Company, and may
be  determined as of a date not more than (sixty) 60 days prior to the happening
of an event for which such determination is being made.

         The term "Debt" means any outstanding debt for money borrowed evidenced
by notes, debentures, bonds, or other securities.

         The term "Net  Tangible  Assets" means the amount shown as total assets
on the  consolidated  balance  sheet of the  Company,  less the  following:  (i)
intangible assets  including,  but without  limitation,  such items as goodwill,
trademarks,  trade names, patents, and unamortized debt discount and expense and
other  regulatory  assets  carried  as an  asset on the  Company's  consolidated
balance sheet; and (ii) appropriate adjustments,  if any, on account of minority
interests.
                                        7

         Net Tangible  Assets shall be determined in accordance  with  generally
accepted accounting  principles and practices applicable to the type of business
in which  the  Company  is  engaged  and that are  approved  by the  independent
accountants  regularly  retained by the Company,  and may be  determined as of a
date not more than (sixty) 60 days prior to the happening of the event for which
such determination is being made.

         The term  "Operating  Property" means (i) any interest in real property
owned by the Company and (ii) any asset owned by the Company that is depreciable
in accordance with generally accepted accounting principles.

         The term "Sale and Lease-Back  Transaction"  means any arrangement with
any person  providing for the leasing to the Company of any  Operating  Property
(except for temporary leases for a term,  including any renewal thereof,  of not
more than forty-eight (48) months),  which Operating  Property has been or is to
be sold or transferred by the Company to such person.

         The  term  "Value"  means,  with  respect  to  a  Sale  and  Lease-Back
Transaction,  as of any particular  time, the amount equal to the greater of (1)
the net proceeds to the Company from the sale or transfer of the property leased
pursuant to such Sale and  Lease-Back  Transaction  or (2) the net book value of
such property,  as determined in accordance with generally  accepted  accounting
principles by the Company at the time of entering into such Sale and  Lease-Back
Transaction,  in either case  multiplied  by a fraction,  the numerator of which
shall be equal to the number of full years of the term of the lease that is part
of such Sale and Lease-Back  Transaction  remaining at the time of determination
and the  denominator of which shall be equal to the number of full years of such
term, without regard, in any case, to any renewal or extension options contained
in such lease.

                                  ARTICLE THREE

                          FORM OF SENIOR NOTE DUE 1999

         SECTION 301. The Senior Notes Due 1999 and the Trustee's certificate of
authentication to be endorsed are to be substantially in the following forms:

Form of Face of Note.

UNLESS THIS  CERTIFICATE  IS PRESENTED BY AN  AUTHORIZED  REPRESENTATIVE  OF THE
DEPOSITORY  TRUST COMPANY,  A NEW YORK  CORPORATION  ("DTC"),  TO ARIZONA PUBLIC
SERVICE COMPANY OR ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE, OR PAYMENT,
AND ANY  CERTIFICATE  ISSUED IS  REGISTERED IN THE NAME OF CEDE & CO. OR IN SUCH
OTHER  NAME AS IS  REQUESTED  BY AN  AUTHORIZED  REPRESENTATIVE  OF DTC (AND ANY
PAYMENT  IS MADE TO CEDE & CO. OR TO SUCH  OTHER  ENTITY AS IS  REQUESTED  BY AN
AUTHORIZED REPRESENTATIVE OF DTC), ANY TRANSFER, PLEDGE, OR OTHER
                                        8

USE HEREOF FOR VALUE OR  OTHERWISE  BY OR TO ANY PERSON IS WRONGFUL  INASMUCH AS
THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.


                         ARIZONA PUBLIC SERVICE COMPANY

                           6.72% Senior Notes Due 1999



No.                                                                  $50,000,000
    -----                                                       CUSIP No.
                                                                         -------

      Arizona Public Service Company,  a corporation duly organized and existing
under the laws of Arizona (herein called the "Company",  which term includes any
successor  Person  under  the  Indenture  hereinafter  referred  to),  for value
received,  hereby  promises to pay to Cede & Co.,  or  registered  assigns,  the
principal  sum of Fifty  Million  Dollars on April 1, 1999,  and to pay interest
thereon from April 10, 1997 or from the most recent  Interest  Payment Date with
respect to which interest has been paid or duly provided for,  semi-annually  on
April 1 and October 1 in each year,  commencing  October 1, 1997, at the rate of
6.72% per  annum,  until the  principal  hereof  is paid or made  available  for
payment,  provided that any principal  and premium,  and any such  instalment of
interest,  which is overdue  shall bear  interest at the rate of 6.72% per annum
(to the extent that the payment of such interest shall be legally  enforceable),
from the dates such  amounts are due until they are paid or made  available  for
payment,  and such interest shall be payable on demand. The interest so payable,
and punctually paid or duly provided for, on any Interest  Payment Date will, as
provided  in such  Indenture,  be paid to the Person in whose name this Note (or
one or more  Predecessor  Notes) is  registered  at the close of business on the
Regular Record Date for such interest,  which shall be the March 15 or September
15 (whether or not a Business  Day),  as the case may be,  next  preceding  such
Interest Payment Date. Any such interest not so punctually paid or duly provided
for will forthwith cease to be payable to the Holder on such Regular Record Date
and may  either be paid to the  Person  in whose  name this Note (or one or more
Predecessor  Notes) is registered  at the close of business on a Special  Record
Date for the  payment of such  Defaulted  Interest  to be fixed by the  Trustee,
notice  whereof  shall be given to Holders of Notes of this series not less than
10 days prior to such Special  Record Date,  or be paid at any time in any other
lawful manner not inconsistent with the requirements of any securities  exchange
on which the Notes of this series may be listed,  and upon such notice as may be
required by such exchange, all as more fully provided in said Indenture.

      Payment of the  principal of (and  premium,  if any) and such  interest on
this Note will be made at the  office or agency of the  Company  maintained  for
that purpose in The City of New
                                        9

York, in such coin or currency of the United States of America as at the time of
payment is legal  tender for  payment of public  and  private  debts;  provided,
however,  that at the option of the Company  payment of interest  may be made by
check mailed to the address of the Person entitled thereto as such address shall
appear in the Note Register.

      Reference is hereby made to the further  provisions of this Note set forth
below,  which further  provisions shall for all purposes have the same effect as
if set forth at this place.

      Unless the certificate of  authentication  hereon has been executed by the
Trustee referred to on the reverse hereof by manual  signature,  this Note shall
not be entitled to any benefit under the Indenture or be valid or obligatory for
any purpose.

      IN WITNESS  WHEREOF,  the Company has caused  this  instrument  to be duly
executed under its corporate seal.

                                             ARIZONA PUBLIC SERVICE COMPANY


                                        By
                                          -------------------------------------




Attest:


- ---------------------------------

Form of Reverse of Note.

      This Note is one of a duly  authorized  issue of securities of the Company
(herein called the "Notes"), issued and to be issued in one or more series under
an  Indenture,  dated as of November  15, 1996 (herein  called the  "Indenture",
which term shall have the meaning  assigned to it in such  instrument),  between
the Company and The Bank of New York, as Trustee  (herein  called the "Trustee",
which term includes any successor trustee under the Indenture), and reference is
hereby  made  to  the  Indenture  for a  statement  of  the  respective  rights,
limitations  of rights,  duties and  immunities  thereunder of the Company,  the
Trustee  and the Holders of the Notes and of the terms upon which the Notes are,
and are to be,  authenticated  and  delivered.  This  Note is one of the  series
designated  on the  face  hereof,  limited  in  aggregate  principal  amount  to
$50,000,000.

      Prior to the  Release  Date (as  hereinafter  defined),  this Note will be
secured by First Mortgage Bonds, Senior Note Series B (the "Senior Note Series B
Bonds")  delivered  by the Company to the Trustee for the benefit of the Holders
of the series of Notes of which this Note
                                       10

is a part,  issued  under the  Mortgage  and Deed of Trust,  dated as of July 1,
1946,  from the  Company  to The Bank of New York,  as  successor  trustee  (the
"Mortgage  Trustee"),  as  supplemented  and  amended  (the  "First  Mortgage").
Reference is made to the First Mortgage for a description of property  mortgaged
and pledged, the nature and extent of the security, the rights of the holders of
the first mortgage bonds under the First Mortgage and of the Mortgage Trustee in
respect thereof, the duties and immunities of the Mortgage Trustee and the terms
and  conditions  upon which the Senior  Note  Series B Bonds are secured and the
circumstances under which additional first mortgage bonds may be issued.

      FROM AND AFTER SUCH TIME AS ALL FIRST  MORTGAGE  BONDS  (OTHER THAN SENIOR
NOTE FIRST MORTGAGE  BONDS,  AS SUCH TERM IS DEFINED IN THE INDENTURE) HAVE BEEN
RETIRED  THROUGH  PAYMENT,  REDEMPTION  OR  OTHERWISE  AT,  BEFORE  OR AFTER THE
MATURITY  THEREOF (THE "RELEASE  DATE"),  THE SENIOR NOTE FIRST  MORTGAGE  BONDS
SHALL CEASE TO SECURE THE NOTES IN ANY MANNER.

      The Notes of this series are subject to  redemption  upon not less than 30
days' notice by mail at any time at the option of the Company,  in whole or from
time  to  time  in  part,  at a  redemption  price  equal  to the sum of (i) the
principal  amount of the Notes (or portion  thereof) being redeemed plus accrued
interest  thereon  to the  redemption  date and (ii) the  Make-Whole  Amount (as
defined  below),  if  any,  with  respect  to  the  Notes  being  redeemed  (the
"Redemption Price").

      If notice has been given as  provided in the  Indenture  and funds for the
redemption of any Notes (or any portion  thereof)  called for  redemption  shall
have been made available on the redemption date referred to in such notice, such
Notes (or any portion thereof) will cease to bear interest on the date fixed for
such  redemption  specified  in such notice and the only right of the Holders of
such Notes will be to receive payment of the Redemption Price.

      Notice of any optional  redemption of Notes of this series (or any portion
thereof) will be given to Holders at their  addresses,  as shown in the security
register  for such Notes,  not more than 60 nor less than 30 days prior,  to the
date fixed for redemption.  The notice of redemption  will specify,  among other
items,  the Redemption  Price and the principal amount of the Notes held by such
Holder to be  redeemed.  If less than all of the Notes are to be redeemed at the
option of the Company, the Trustee shall select, in such manner as it shall deem
fair and  appropriate,  the  portion of such Notes to be redeemed in whole or in
part.

      As used herein:

         "Make-Whole  Amount" means, in connection with any optional  redemption
      of any Notes, the excess, if any, of (i) the aggregate present value as of
      the date of such redemption of each dollar of principal being redeemed and
      the  amount of  interest  (exclusive  of  interest  accrued to the date of
      redemption) that would have been payable in respect of each such dollar if
      such  redemption  had not  been  made,  determined  by  discounting,  on a
      semi-annual basis, such
                                       11

      principal and interest at the  Reinvestment  Rate (determined on the third
      Business Day  preceding  the date such notice of redemption is given) from
      the respective  dates on which such principal and interest would have been
      payable  if such  redemption  had not been made,  over (ii) the  aggregate
      principal amount of the Notes being redeemed.

         "Reinvestment  Rate" means 0.10% plus the arithmetic mean of the yields
      under the  respective  heading "Week Ending"  published in the most recent
      Statistical  Release under the caption "Treasury Constant  Maturities" for
      the maturity (rounded to the nearest month) corresponding to the remaining
      life to maturity,  as of the payment date of the principal being redeemed.
      If no maturity  exactly  corresponds to such maturity,  yields for the two
      published maturities most closely  corresponding to such maturity shall be
      calculated  pursuant  to  the  immediately   preceding  sentence  and  the
      Reinvestment  Rate shall be interpolated or extrapolated  from such yields
      on a straight-line basis, rounding in each of such relevant periods to the
      nearest month. For the purpose of calculating the  Reinvestment  Rate, the
      most  recent   Statistical   Release   published  prior  to  the  date  of
      determination of the Make-Whole Amount shall be used.

         "Statistical   Release"  means  the  statistical   release   designated
      "H.15(519)" or any successor  publication which is published weekly by the
      Federal  Reserve System and which  establishes  yields on actively  traded
      United States government  securities adjusted to constant maturities,  or,
      if  such  statistical  release  is  not  published  at  the  time  of  any
      determination under the Indenture,  then such other reasonably  comparable
      index which shall be designated by the Company.

      The Notes of this series will not be subject to any sinking fund.

      In the event of  redemption of this Note in part only, a new Note or Notes
of this  series  and of like tenor for the  unredeemed  portion  hereof  will be
issued in the name of the Holder hereof upon the cancellation hereof.

      The Indenture contains provisions for defeasance at any time of the entire
indebtedness of this Note or certain restrictive covenants and Events of Default
with respect to this Note, in each case upon compliance with certain  conditions
set forth in the Indenture.

      If an Event of Default  with  respect to Notes of this series  shall occur
and be continuing, the principal of the Notes of this series may be declared due
and payable in the manner and with the effect provided in the Indenture.

      If an Event of Default  with  respect to Notes of this series  shall occur
and be continuing, the principal of the Notes may be declared due and payable in
the  manner  and with the  effect  provided  in the  Indenture  and,  upon  such
declaration, the Trustee can demand the acceleration of the payment of principal
of the Senior Note Series B Bonds as provided in the Indenture.
                                       12

      The Indenture permits,  with certain  exceptions as therein provided,  the
amendment  thereof and the  modification  of the rights and  obligations  of the
Company and the rights of the Holders of the Notes of each series to be affected
under the  Indenture at any time by the Company and the Trustee with the consent
of the  Holders  of a  majority  in  principal  amount  of the Notes at the time
Outstanding  of  each  series  to  be  affected.  The  Indenture  also  contains
provisions  permitting the Holders of specified  percentages in principal amount
of the Notes of each series at the time Outstanding, on behalf of the Holders of
all Notes of such  series,  to waive  compliance  by the  Company  with  certain
provisions of the  Indenture  and certain past defaults  under the Indenture and
their consequences.  Any such consent or waiver by the Holder of this Note shall
be conclusive  and binding upon such Holder and upon all future  Holders of this
Note and of any Note  issued  upon the  registration  of  transfer  hereof or in
exchange therefor or in lieu hereof,  whether or not notation of such consent or
waiver is made upon this Note.

      As provided in and subject to the provisions of the Indenture,  the Holder
of this Note shall not have the right to institute any  proceeding  with respect
to the  Indenture  or for the  appointment  of a receiver  or trustee or for any
other  remedy  thereunder,  unless such Holder shall have  previously  given the
Trustee  written  notice of a  continuing  Event of Default  with respect to the
Notes of this series,  the Holders of not less than 25% in  principal  amount of
the Notes of this series at the time Outstanding shall have made written request
to the Trustee to institute  proceedings  in respect of such Event of Default as
Trustee and offered the Trustee reasonable indemnity,  and the Trustee shall not
have  received  from the Holders of a majority in  principal  amount of Notes of
this series at the time Outstanding a direction  inconsistent with such request,
and shall  have  failed to  institute  any such  proceeding,  for 60 days  after
receipt of such notice, request and offer of indemnity.  The foregoing shall not
apply to any suit  instituted by the Holder of this Note for the  enforcement of
any payment of  principal  hereof or any premium or interest  hereon on or after
the respective due dates expressed herein.

      No reference  herein to the  Indenture and no provision of this Note or of
the  Indenture  shall alter or impair the  obligation  of the Company,  which is
absolute and unconditional, to pay the principal of and any premium and interest
on this Note at the times,  place and rate, and in the coin or currency,  herein
prescribed.

      As provided in the  Indenture and subject to certain  limitations  therein
set forth,  the transfer of this Note is registrable in the Note Register,  upon
surrender of this Note for  registration  of transfer at the office or agency of
the Company in any place where the  principal of and any premium and interest on
this Note are payable,  duly endorsed by, or accompanied by a written instrument
of transfer in form  satisfactory  to the  Company and the Note  Registrar  duly
executed by, the Holder hereof or his attorney duly  authorized in writing,  and
thereupon one or more new Notes of this series and of like tenor,  of authorized
denominations and for the same aggregate principal amount, will be issued to the
designated transferee or transferees.

      The Notes of this series are  issuable  only in  registered  form  without
coupons  in  denominations  of $1,000  and any  integral  multiple  thereof.  As
provided in the Indenture and subject to certain  limitations therein set forth,
Notes of this series are exchangeable  for a like aggregate  principal amount of
Notes of this series and of like tenor of a different  authorized  denomination,
as requested by the Holder surrendering the same.
                                       13

      No service charge shall be made for any such  registration  of transfer or
exchange,  but the Company may require  payment of a sum sufficient to cover any
tax or other governmental charge payable in connection therewith.

      Prior to due presentment of this Note for  registration  of transfer,  the
Company,  the  Trustee and any agent of the Company or the Trustee may treat the
Person in whose  name  this  Note is  registered  as the  owner  hereof  for all
purposes,  whether or not this Note be overdue,  and neither  the  Company,  the
Trustee nor any such agent shall be affected by notice to the contrary.

      All terms used in this Note which are defined in the Indenture  shall have
the meanings assigned to them in the Indenture.

Form of Trustee's Certificate of Authentication.

                          CERTIFICATE OF AUTHENTICATION

   This is one of the Notes of the series designated  therein referred to in the
within-mentioned Indenture.

   Dated:
                                                           THE BANK OF NEW YORK,
                                                                      As Trustee


                                                 By
                                                    ----------------------------
                                                            Authorized Signatory





                                  ARTICLE FOUR

                     ORIGINAL ISSUE OF SENIOR NOTES DUE 1999

         SECTION 401. Senior Notes Due 1999 in the aggregate principal amount of
$50,000,000,  may, upon execution of this Second Supplemental Indenture, or from
time to time thereafter, be executed by the Company and delivered to the Trustee
for  authentication,  and the Trustee shall thereupon  authenticate  and deliver
said Notes to or upon the written order of the Company,  signed by its Chairman,
its  President,  or  any  Vice  President  and  its  Treasurer  or an  Assistant
Treasurer, without any further action by the Company.
                                       14

                                  ARTICLE FIVE

                           PAYING AGENT AND REGISTRAR

         SECTION  501.  The Bank of New York will be the  Paying  Agent and Note
Registrar for the Senior Notes Due 1999.

                                   ARTICLE SIX

                                SUNDRY PROVISIONS

         SECTION  601.  Except as  otherwise  expressly  provided in this Second
Supplemental  Indenture  or in the form of Senior  Notes  Due 1999 or  otherwise
clearly  required by the context hereof or thereof,  all terms used herein or in
said form of Senior Notes Due 1999 that are defined in the Indenture  shall have
the several meanings respectively assigned to them thereby.

         SECTION 602. The Indenture, as supplemented by this Second Supplemental
Indenture,  is  in  all  respects  ratified  and  confirmed,   and  this  Second
Supplemental  Indenture  shall be deemed part of the Indenture in the manner and
to the extent herein and therein provided.

         SECTION 603. The Trustee  hereby  accepts the trusts  herein  declared,
provided, created,  supplemented, or amended and agrees to perform the same upon
the terms and conditions herein and in the Indenture, as heretofore supplemented
and amended, set forth and upon the following terms and conditions:

         The Trustee shall not be responsible in any manner whatsoever for or in
respect of the validity or sufficiency of this Second Supplemental  Indenture or
for or in respect of the recitals  contained  herein,  all of which recitals are
made by the  Company  solely.  In  general,  each and every  term and  condition
contained in Article Seven of the Indenture shall apply to and form part of this
Second Supplemental Indenture with the same force and effect as if the same were
herein set forth in full with such omissions,  variations,  and  insertions,  if
any, as may be  appropriate  to make the same conform to the  provisions of this
Second Supplemental Indenture.

                        ---------------------------------

         This instrument may be executed in any number of counterparts,  each of
which so executed shall be deemed to be an original,  but all such  counterparts
shall together constitute but one and the same instrument.
                                       15

         IN  WITNESS  WHEREOF,  the  parties  hereto  have  caused  this  Second
Supplemental Indenture to be duly executed, and their respective corporate seals
to be  hereunto  affixed  and  attested,  all as of the day and year first above
written.


                                        ARIZONA PUBLIC SERVICE COMPANY



                                        By: Nancy E. Felker
                                           ---------------------------------
                                            Nancy E. Felker
                                            Treasurer

Attest:


Betsy A. Pregulman
- ---------------------------------
Betsy A. Pregulman
Associate Secretary

                                        THE BANK OF NEW YORK, as Trustee



                                        By: Walter N. Gitlin
                                           ---------------------------------
                                            Walter N. Gitlin
                                            Vice President

Attest:

Stephen J. Giurlando
- ---------------------------------
Stephen J. Giurlando
Assistant Vice President
                                       16

STATE OF ARIZONA   )
                   ) ss:
COUNTY OF MARICOPA )

         On the 9th day of April,  1997,  before  me  personally  came  Nancy E.
Felker, to me known, who, being by me duly sworn, did depose and say that she is
the  Treasurer  of  Arizona  Public  Service  Company,  one of the  corporations
described in and which  executed the  foregoing  instrument;  that she knows the
seal of said  corporation;  that the seal  affixed  to said  instrument  is such
corporate seal; that it was so affixed by authority of the Board of Directors of
said corporation; and that she signed her name thereto by like authority.

                                        
                                               Maria R. Marrs
                                 -----------------------------------------------
                                               NOTARY PUBLIC

My Commission Expires:

July 21, 1998
- ------------------------
                                       17

STATE OF NEW YORK            )
                             ) ss:
COUNTY OF NEW YORK           )

         On the 8th day of April,  1997,  before me  personally  came  Walter N.
Gitlin, to me known, who, being by me duly sworn,  did depose and say that he is
the Vice President of The Bank of New York, one of the corporations described in
and which  executed  the  foregoing  instrument;  that he knows the seal of said
corporation;  that the seal affixed to said  instrument is such corporate  seal;
that  it was so  affixed  by  authority  of  the  Board  of  Directors  of  said
corporation; and that he signed his name thereto by like authority.


                                               William J. Cassels
                                 -----------------------------------------------
                                                  NOTARY PUBLIC

My Commission Expires:

     May 16, 1998
- ------------------------
                                       18