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                                                                   EXHIBIT 10.11

                          RETENTION INCENTIVE AGREEMENT


         THIS RETENTION INCENTIVE AGREEMENT dated as of June 1, 1999 by and
between American Telecasting, Inc. (the "Company") and Charles A. Spann, (the
"Employee").

                                   WITNESSETH:

         WHEREAS, the Company recognizes the competitive nature of the market
for executive and managerial talent; and

         WHEREAS, the Company has determined that appropriate steps should be
taken to encourage certain key executives and managers to remain employed by the
Company by providing for certain benefits;

         NOW, THEREFORE, the parties hereto, intending to be legally bound
hereby, agree to the following:

         1.       Definitions. The capitalized terms used herein shall have the
                  meanings ascribed to them below.

                  (a)      "Cause" shall mean (A) the willful and continued
                           failure by the Employee substantially to perform the
                           Employee's duties with the Company (other than any
                           such failure resulting from the Employee's incapacity
                           due to physical or mental illness) as determined by
                           the Board of Directors of the Company (the "Board"),
                           after a demand for substantial performance is
                           delivered to the Employee by the Company, which
                           demand specifically identifies the manner in which
                           the Company believes that the Employee has not
                           substantially performed the Employee's duties or (B)
                           the willful engaging by the Employee in misconduct
                           which is demonstrably and materially injurious to the
                           Company, momentarily or otherwise. Notwithstanding
                           the foregoing, the Employee's employment shall not be
                           deemed to have been terminated for Cause unless and
                           until there shall have been delivered to the Employee
                           by the Company a copy of a Notice of a Termination
                           authorized by the Board stating that in the good
                           faith opinion of the Board the Employee is guilty of
                           conduct set forth in clauses (A) or (B) above and
                           specifying the particulars there of in detail.

                  (b)      "Disability" shall be deemed the reason for the
                           termination by the Company of the Employee's
                           employment, if, as a result of the Employee's
                           incapacity due to physical or mental illness, the
                           Employee shall have been absent from the full-time
                           performance of the Employee's duties with the Company
                           for a period of six (6) consecutive months.


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                  (c)      "Material Employment Change" shall mean any of the
                           following:

                           (i)      a reduction in the Employee's base or other
                                    compensation as in effect on the date hereof
                                    or as the same may be increased from time to
                                    time during the term of this Agreement; or

                           (ii)     the relocation of the Employee's current
                                    principal place of employment to a location
                                    that is more than 60 miles from the
                                    Employee's current principal place of
                                    employment or requiring the Employee to be
                                    based anywhere other than such principal
                                    place of employment (or permitted relocation
                                    thereof) except for required travel on the
                                    Company's business to an extent
                                    substantially consistent with the Employee's
                                    present business travel obligations.

                           (iii)    The consummation of the transaction
                                    contemplated by the Agreement and Plan of
                                    Merger by and among Sprint Corporation, DD
                                    Acquisition Corp. and American Telecasting,
                                    Inc. dated as of April 26, 1999, any
                                    transfer of payroll functions from the
                                    Company to Sprint Corporation (so that the
                                    Employee shall become an employee of Sprint
                                    Corporation or shall be paid by Sprint
                                    Corporation) or any change in group
                                    insurance, 40l(k) or other benefits shall
                                    not constitute a Material Employment Change.

         2.       Retention Incentive.

                  (a)      Upon the earliest to occur of the following dates and
                           events while the Employee is employed by the Company,
                           the Employee shall be entitled to receive a lump sum
                           cash payment of $25,000 (the "Retention Incentive"):

                           (i)      the termination of the Employee's employment
                                    by the Company other than for Cause;

                           (ii)     the termination of the Employee's employment
                                    by the Employee following the occurrence of
                                    a Material Employment Change;

                           (iii)    June 30, 2000; or

                           (iv)     the Employee's death or Disability.

                  (b)      If the Employee's employment is terminated prior to
                           June 30, 2000 by the Company for Cause or by the
                           Employee other than (i) following a Material
                           Employment Change or (ii) on account of the
                           Employee's death or Disability, no Retention
                           Incentive shall be paid to the Employee.


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                  (c)      In addition to the Retention Incentive, if the
                           Employee's employment with the Company terminates
                           under circumstances enumerated in Item
                           (2)(a)(i)-(iii) above on or before December 31, 1999,
                           then the Employee shall be entitled to receive an
                           additional lump sum cash payment equivalent to twelve
                           (12) months of compensation at the highest base rate
                           of salary in effect at the Company for the Employee
                           between the date of this Agreement and December 31,
                           1999. This obligation supersedes any commitments by
                           the Company under any prior Retention Agreement.

         3.       No Effect on Other Contractual Rights. The provisions of this
                  Agreement, and any payment provided for hereunder, shall not
                  reduce any amounts otherwise payable, or in any way diminish
                  the Employee's existing rights or rights (or rights which
                  would accrue solely as a result of the passage of time) under
                  any employee benefit plan or employment agreement or other
                  contract, plan or arrangement nor shall any amounts payable
                  hereunder be considered in determining the amount of benefits
                  payable to the Employee under any such plan, agreement or
                  contract.

         4.       Successor to the Company.

                  (a)      This Agreement shall be binding on the Company's
                           successors and assigns.

                  (b)      This Agreement shall inure to the benefit of and be
                           enforceable by the Employee's personal and legal
                           representatives, executors, administrators,
                           successors, heirs, distributees, devisees and
                           legatees. If the Employee should die while any
                           amounts are still payable to the Employee hereunder,
                           all such amounts, unless otherwise provided herein,
                           shall be paid in accordance with the terms of this
                           Agreement to the Employee's personal representative,
                           devisee, legatee, or other designee or, if there be
                           no such designee, to the Employee's estate.

         5.       Notice. For purposes of this Agreement, notices and all other
                  communications provided for in this Agreement shall be in
                  writing and shall be deemed to have been duly given when
                  delivered or mailed by United States registered mail, return
                  receipt requested, postage prepaid as follows:

                                    If to the Company:

                                    5575 Tech Center Drive, Suite 300
                                    Colorado Springs, CO  80919
                                    Attention:  President


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                                    With a copy to:

                                    Skadden, Arps, Slate, Meagher & Flom LLP
                                    919 Third Avenue
                                    New York, NY 10022
                                    Attention:  Randall H. Doud
                                    If to the Employee:

                                    Charles A. Spann
                                    5385 Evening Light Crt.
                                    Colorado Springs, CO  80917

                  or such other address as either party may have furnished to
                  the other in writing in accordance herewith, except that
                  notices of change of address shall be effective only upon
                  receipt.

         6.       Amendment Waiver. No provision of this Agreement may be
                  modified, waived or discharged unless such waiver,
                  modification or discharge is agreed to in writing signed by
                  the Employee and the Company. No waiver by either party hereto
                  at any time of any breach of the other party hereto of, or
                  compliance with, any condition or provision of this Agreement
                  to be performed by such party shall be deemed a waiver of
                  similar or dissimilar provisions or conditions at the same or
                  at any prior or subsequent time. No agreements or
                  representations, oral or otherwise, express or implied, with
                  respect to the subject matter hereof have been made by either
                  party which are not set forth expressly in this Agreement.

         7.       Validity. The invalidity or unenforceability of any provision
                  of this Agreement shall not affect the validity or enforce
                  ability of any other provision of this Agreement, which shall
                  remain in full force and effect.

         8.       Counterparts. This Agreement may be executed in one or more
                  counterparts, each of which shall be deemed to be an original
                  but all of which together will constitute one and the same
                  instrument.

         9.       Governing Law. This Agreement shall be governed by and
                  construed in accordance with the laws of the State of
                  Colorado.


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         IN WITNESS WHEREOF, the parties have executed this Agreement as of the
date first above written.


                                         American Telecasting, Inc.



                                         ---------------------------------------
                                         Robert D. Hostetler
                                         President and Chief Executive Officer


                                         Employee



                                         ---------------------------------------
                                         Charles A. Spann


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