In the
 United States Court of Appeals
               For the Seventh Circuit
                          ____________

Nos. 04-2877, 04-3051, 04-3052, 04-3053,
     04-3087, 04-3088, 04-3089 & 04-3090
DIANA L. ALINSKY, individually and
as personal representative of the
Estate of Paul Alinsky, deceased, et al.,
                                                Plaintiffs-Appellants,
                                  v.


UNITED STATES OF AMERICA,
                                                 Defendant-Appellee.
                          ____________
          Appeals from the United States District Court for
          the Northern District of Illinois, Eastern Division.
                Nos. 98 C 6189, 99 C 1738, 99 C 2447
                & 99 C 2883—James B. Zagel, Judge.
                          ____________
      ARGUED FEBRUARY 10, 2005—DECIDED JULY 13, 2005
                          ____________



  Before MANION, EVANS, and SYKES, Circuit Judges.
  MANION, Circuit Judge. On July 19, 1997, two private
airplanes crashed in mid-air over the Chicago lakefront,
killing all seven occupants. At the time of the crash, both
airplanes were receiving air traffic services from Meigs Field
Air Traffic Control Tower, operated by a private contractor
2                                         Nos. 04-2877, et al.

to the Federal Aviation Administration (“FAA”). The estates
and relatives of the decedents filed multiple lawsuits
against a number of defendants in state and federal court.
This case pertains to the estates’ suits against the United
States under the Federal Tort Claim Act. The district court
granted the United States summary judgment on several
claims and held a trial on others. Following the trial, the
district court ruled in favor of the United States on the
remaining claims. The plaintiffs appeal.


                              I.
   On July 19, 1997, two airplanes collided in mid-air ap-
proximately three miles south of Meigs Field in Chicago,
                                                     1
Illinois. All seven occupants of the planes perished.
  At the time of the collision, Renee Toone was staffing the
air traffic control tower at Meigs Field. Toone worked for
Midwest Air Traffic Control, Inc., a private contractor hired
by the FAA to provide air traffic control services for Meigs
Field. For purposes of appeal, the parties assume that
Toone’s failure to inform the pilots of the two planes that
they were on a collision course was the cause of the fatal
crash.
  Following the crash, the estates and relatives of the de-
cedents filed numerous suits against various parties, in-
cluding the City of Chicago, Midwest, Renee Toone, the
estates of the pilots of the airplanes which collided, and the
pilot of a third airplane flying near Meigs Field. Most of the
state court cases were settled, but one was tried. A jury
found the pilot of a third airplane, who at the time of the


1
 They were Paul Alinsky, Jeffrey Walker, Colleen Canty, Sheba
Van Pelt, Taiciana Phillips, Donetta Ladd, and Barbara Polka.
Nos. 04-2877, et al.                                            3

collision was communicating with Toone about a landing
gear problem, liable in the amount of $2,195,416. Walker v.
Segal, Cook Cty. Cir. Ct. No. 2002-L-2169. The present case
involves the estates’ consolidated suit against the
United States under the Federal Tort Claim Act, 28 U.S.C.
§§ 1346 et seq. (“FTCA”).
   The plaintiffs’ FTCA suit alleged claims under multiple
theories. First, the plaintiffs sought to hold the United States
liable, arguing the United States had a non-delegable duty
to provide air traffic control services and was thus responsi-
ble for Toone’s negligence. The plaintiffs also alleged the
United States was liable for its own negligence by allowing
an allegedly untrained and unqualified controller to staff
Meigs tower. Finally, the plaintiffs alleged that the
United States was liable because it negligently delayed
approving additional staffing at Meigs.
  Initially, we must address the timeliness of this appeal. As
noted above, the plaintiffs’ cases were consolidated. None-
theless, in issuing its final decision on the matter, the district
court issued four separate Memorandum Opinion and
Orders, identical except for the caption and the names of the
parties. On January 27, 2004, in three of the four cases, the
district court also entered a separate final judgment in favor
of the United States, each of which was docketed two days
later. However, in the lead case, Alinsky, No. 98-CV-6189,
the district court did not enter a separate judgment, as the
final judgment form was inadvertently attached to the last
page of the corresponding Memorandum Opinion and
Order. Although the Memorandum Opinion and Order in
the Alinksy case was docketed, the judgment form was not
separately entered on the docket, as was done in the other
three cases. It was not until June 17, 2004, that the district
court entered a separate judgment in the lead case of
Alinksy, after which all of the plaintiffs filed a notice of
appeal on July 21, 2004.
4                                            Nos. 04-2877, et al.

   Federal Rule of Appellate Procedure 4(a)(1)(B) provides
that when the United States is a party to the action, the
notice of appeal must be filed “within 60 days after the
judgment or order appealed from is entered.” The district
court docketed the judgment against three of the plaintiffs
on January 29, 2004, but these three plaintiffs did not file a
notice of appeal until July 21, 2004, after the district court
had entered a separate judgment in the Alinsky case on June
17, 2004. However, this court held in Sandwiches, Inc. v.
Wendy’s Int’l, Inc., 

(7th Cir. 1987), that where
two cases are consolidated for all purposes, a single judg-
ment not covering all claims and parties is not appealable
                                              2
absent a ruling under Fed. R. Civ. P. 54(b). 

Be-
cause the district court consolidated these cases for discov-
ery and trial, we conclude that the sixty-day time period for
filing a notice of appeal did not begin to run until a final
judgment was entered for all four cases.
  The question then becomes when did the district court
“enter” a final judgment in the Alinsky case. As noted above,
on January 27, 2004, the district court issued its Memoran-
dum Opinion and Order ruling in favor of the Untied States
in the Alinksy case, and that order was docketed on January
29, 2004. However, Fed. R. Civ. P. 58(a)(1) provides that
“[e]very judgment and amended judgment must be set forth
on a separate document . . . .” The district court had also
prepared a Rule 58 judgment in the Alinsky case, but that


2
  Fed. R. Civ. P. 54(b) provides: “When more than one claim for
relief is presented in an action, whether as a claim, counterclaim,
crossclaim, or third-party claim or when multiple parties are
involved, the court may direct the entry of final judgment as to
one or more but fewer than all of the claims or parties only upon
an express determination that there is no just reason for delay
and upon an express direction for the entry of judgment.”
Nos. 04-2877, et al.                                         5

form was mistakenly stapled to the end of
the Memorandum Opinion and Order and not separately
docketed at that time. Because the judgment form was not
a separate document, as required under Rule 58(a)(1), we
conclude that judgment in Alinksy was not “entered” on
January 29, 2004. See Fed. R. Civ. P. 58(b)(2) (“Judgment is
entered for purposes of these rules: if Rule 58(a)(1) requires
a separate document, when it is entered in the civil docket
under Rule 79(a) and when the earlier of these events oc-
curs: (A) when it is set forth on a separate document, or (B)
when 150 days have run from entry in the civil docket under
Rule 79(a)”).
   The government acknowledges that if the judgment form
attached to the Memorandum Opinion and Order is not
considered a separate document, then the plaintiffs’ appeal
is timely because, under Rule 58(b)(2)(B), the time for filing
an appeal would not start until June 28, 2004 (150 days from
January 29, 2004), and the plaintiffs would have sixty days
from that date to file a notice of appeal. The plaintiffs take
issue with the government’s interpretation of Rule 58(b)(2),
claiming that the 150-day provision did not start on
January 29, 2004, because the district court did not docket a
“separate document” on that date. Rather, the plaintiffs
maintain that the time for filing an appeal did not begin to
run until June 17, 2004, when the district court entered a
separate judgment in the Alinsky case. It is unclear why the
plaintiffs take issue with the government’s view because,
under the United States’ interpretation, the time for filing an
appeal began at a later date. However, we need not worry
ourselves with this question or resolve the dispute over the
interpretation of Rule 58(b)(2), because under either reading,
the notices of appeal filed on July 21, 2004, were timely.
6                                         Nos. 04-2877, et al.

                              II.
   That brings us to the merits of this appeal. On appeal, the
plaintiffs argue that the district court erred in holding that
it lacked jurisdiction to consider their claim against the
United States under the FTCA based on Toone’s alleged
negligence. The FTCA provides a limited waiver of the
federal government’s sovereign immunity. The FTCA grants
federal courts jurisdiction over damages claims against the
United States “for injury or loss of property, or personal
injury or death caused by the negligent or wrongful act or
omission of any employee of the Government while acting
within the scope of his office or employment . . . .” 28 U.S.C.
§ 1346(b). An “employee of the government” includes
military personnel and “employees of any federal agency.”
28 U.S.C. § 2671. The term “federal agency” expressly
excludes “any contractor with the United States.” 28 U.S.C.
§ 2671; see also United States v. Orleans, 

, 814
(1976); Logue v. United States, 

, 526-27 (1973).
  In this case, Toone was not an employee of the
United States. Rather, she worked for Midwest Air, an in-
dependent contractor hired by the United States to provide
air traffic control services for Meigs Field. Therefore, under
the FTCA, the district court lacked jurisdiction to consider
any claims against the United States based on Toone’s
negligence.
  The plaintiffs seek to overcome Toone’s status as an
employee of an independent contractor by arguing that the
United States lacked the authority to hire private contractors
to provide air traffic control services. In support of this
position, the plaintiffs cite to 49 U.S.C. App. § 1344(h),
which was in effect at the time of the accident. That section
provided:
    The Secretary may make a contract, on a sole source
    basis, with a State or political subdivision of a State to
Nos. 04-2877, et al.                                          7

    allow the State or subdivision to operate an airport
    traffic control tower classified as a level I (Visual Flight
    Rules) tower if the Secretary decides that the State or
    subdivision has the capability to comply with the
    requirements of this paragraph. The contract shall re-
    quire that the State or subdivision comply with applica-
    ble safety regulations in operating the facility and with
    applicable competition requirements in making a
    subcontract to perform work to carry out the contract.
49 U.S.C. App. § 1344(h).
  The plaintiffs maintain that because this section referred
only to contracts with the State or a political subdivision, the
FAA lacked authority to contract with private organizations
to provide air traffic control services. They further argue
that an amendment to that section (effective in 2003)
confirms their position because Congress subsequently
modified the statute to provide that the FAA may enter into
contracts for air traffic control services with any “qualified
entity.” 49 U.S.C. § 47124(b)(2).
  The FAA, however, does not rely on these statutory
provisions as authority for subcontracting with Midwest.
Rather, the FAA relies on several other statutory grants of
authority, such as 49 U.S.C. § 106(l)(6), which provides:
    The Administrator is authorized to enter into and
    perform such contracts . . . as may be necessary to carry
    out the functions of the Administrator and the
    Administration. The Administrator may enter into such
    contracts . . . with any . . . person, firm, association,
    corporation, or educational institution, on such terms
    and conditions as the Administrator may consider ap-
    propriate.
49 U.S.C. § 106(l)(6). The FAA also relies on 49 U.S.C.
§ 40110, which provides that the Administrator “may
8                                           Nos. 04-2877, et al.

acquire services,” and 49 U.S.C. § 40111, which authorizes
the Administrator to enter contracts for services, including
services for the “operation of facilities and installations.”
  The provisions the FAA cites clearly authorize the FAA to
enter into contracts as necessary, including for services to
operate the air traffic control facilities. Nothing in the
language of 49 U.S.C. § 1344(h) limits this broad grant of
authority. Nor have the plaintiffs pointed to any statutory
provisions which prohibit the FAA from hiring private con-
tractors for air traffic control services. In fact, at the time of
the accident, the FAA had contracted with private contrac-
tors to provide air traffic control services at approximately
130 other air traffic control towers, like Meigs.
   Moreover, we find the plaintiffs’ reliance on 49 U.S.C.
§ 1344(h) misplaced. That section spoke of contracting with
States or political subdivisions, but did not mention private
contractors. Nor did the statute in any way limit the FAA’s
authority to contract with private contractors—an authority
confirmed by other statutory provisions. It would also be
illogical to conclude that Congress intended to prohibit the
FAA from hiring private contractors to provide air traffic
control services where § 1344(h) recognized that the States
and political subdivisions had the authority to subcontract
out services. See 49 U.S.C. § 1344(h) (“The contract shall re-
quire that the State or subdivision comply with applicable
safety regulations in operating the facility and with applicable
competition requirements in making a subcontract to perform
work to carry out the contract.”). For all of these reasons, we
Nos. 04-2877, et al.                                          9

refuse to read the permissive language of § 1344(h) as
prohibitive, or as overcoming the express grant of authority
                                                  3
Congress provided in other statutory provisions.
   Alternatively, the plaintiffs argue that the FAA is nonethe-
less liable for Toone’s conduct because air traffic control
services are nondelegable. In support of their position, the
plaintiffs cite Illinois tort cases holding that a principal is
liable for torts committed by an independent contractor
where the contractor performs abnormally dangerous ac-
tivities because such activities are nondelegable. However,
as the Supreme Court in Logue explained, in adopting the
FTCA’s contractor exception to liability, Congress did not
simultaneously adopt the various state exceptions to the
independent contractor 

. Rather, Con-
gress expressly granted jurisdiction for suits brought against
the United States for its employees’ conduct, and not the
conduct of contractors. State common law principles cannot
overcome this federal statute. See Roditis v. United States, 

, 111 (2d Cir. 1997); Berkman v. United States, 

, 112-13 (4th Cir. 1992); Flynn v. United States, 

, 681-82 (10th Cir. 1980); Alexander v. United States,

, 835 (5th Cir. 1979); Gibson v. United States, 

, 1243-44 (3d Cir. 1977). But see Dickerson, Inc. v.
United States, 

, 1583 (11th Cir. 1989) (holding
that “the independent contractor exception in the FTCA
would not insulate the Government from the contractor’s
negligence if the duty was non-delegable under Florida
law”). Accordingly, the plaintiffs’ attempts to hold the


3
  Furthermore, even if the FAA acted without authority in
contracting with Midwest Air, that would not render Toone an
employee of the United States government, and Congress only
waived immunity for suits brought against United States em-
ployees.
10                                         Nos. 04-2877, et al.

United States liable for Toone’s conduct fail because she was
an employee of Midwest, a private contractor, and not the
United States.
  The plaintiffs also challenge the district court’s decision in
favor of the United States on their remaining negligence
claims. Specifically, the plaintiffs alleged the United States
negligently failed to respond to Midwest’s request for fund-
ing for additional air traffic controllers, and negligently
administered the contract with Midwest by allowing an
allegedly untrained and unqualified controller (Toone) to
stand watch alone.
  First, we consider the plaintiffs’ claim that the FAA was
negligent in failing to approve Midwest’s request for fund-
ing for an additional air traffic controller. To fully under-
stand this claim, we must first explain a few additional
facts. The contract between the FAA and Midwest required
Midwest to take responsibility for staffing and operating the
tower at Meigs in accordance with the staffing plan sub-
mitted by Midwest with its bid to provide air traffic control
services. In its bid, Midwest stated that it would, at times,
staff the tower with a single controller. Midwest, however,
also agreed to increase staffing “with no increase to the
contract price” if it determined that a facility’s staffing
needed to be increased.
  On April 17, 1997, about two months after opening Meigs
Tower with the level of staffing it had designated in its bid,
namely one controller, Midwest requested additional fund-
ing from the FAA’s Regional Point of Contract for contract
towers in the Great Lakes Region so that it could hire
another air traffic controller. Midwest made this request be-
cause it had noticed an increase in traffic at Meigs. The
request was not marked as an emergency request and there-
fore was handled in the routine manner, which meant that
the Regional Office sent a memorandom to the Federal
Nos. 04-2877, et al.                                           11

Contract Tower Program Office at the FAA headquarters in
Washington, D.C., requesting that the contract be modified
to increase staffing at Meigs Tower. The Contract Tower
Program Office then processed this request, which accord-
ing to the manager would normally take between six to
eight weeks, although in an emergency situation the office
has been able to increase staffing within two to three weeks.
Following review by the Contract Tower Program Office,
the FAA officially approved the request for increased
staffing on July 3, 1997, which was a little over two weeks
before the accident.
  The plaintiffs argue that the FAA was negligent in failing
to respond sooner to Midwest’s request for additional air
traffic controllers at Meigs and that the lack of adequate
staffing caused the fatal crash. After a bench trial on this
claim, the district court held that the FAA acted reasonably
in considering the non-emergency request by Midwest for
a contract modification to increase staffing at Meigs Tower.
This court reviews that factual finding for clear error. See
Cerros v. Steel Techs., Inc., 

, 1044 (7th Cir. 2002).
  On appeal, the plaintiffs fail to demonstrate that the
district court’s factual finding was clearly erroneous. They
merely posit that the government should have acted faster
in response to Midwest’s request for additional funding.
However, the evidence established that the FAA had no rea-
son to view the request as an emergency and that the FAA
responded within the regular time frame necessary for the
government to process such requests, and that it approved
additional funding more than two weeks before the acci-
dent. Moreover, the evidence established that Midwest did
not need approval to increase staffing levels at Meigs. As
noted above, Midwest’s contract with the FAA required
Midwest to increase staffing levels if needed. In fact, about
two weeks before the accident, Midwest provided a “quick
12                                           Nos. 04-2877, et al.

response team” to help control traffic at Meigs due to an in-
crease in air traffic related to a weekend convention. There-
fore, even if the FAA should have processed Midwest’s
request for additional funding more promptly, that delay
did not cause the accident because Midwest was required
by the contract with the FAA to assign additional controllers
to the tower, if necessary, with or without funding. Thus,
the FAA’s funding decision did not cause the alleged
                4
understaffing. Accordingly, the district court did not clearly
err in finding in favor of the United States on the plaintiffs’
claim that the United States negligently delayed the approval
of additional funding.
  Finally, the plaintiffs argue that the United States was
negligent because it allowed Midwest to staff the control
tower with Toone who, according to the plaintiffs, was not
qualified to stand watch alone because she had not com-
pleted a required training course and did not have six
months’ experience at Meigs Field. The government re-
sponds that it waived the six-month experience requirement
because Meigs Field had just been reopened and thus it was
impossible for any controller to have six months of experi-
ence at Meigs. As to the training class, the government
points out that the class at issue concerned administrative
                              5
issues and not safety issues, and that Toone had received
equivalent training from Midwest.


4
  Moreover, the evidence established that even had additional
funding been approved, only one controller would have staffed
the tower at the time of the accident because the accident oc-
curred in the evening, and Midwest’s revised staffing plan called
for only one controller after 6:00 p.m.
5
  The plaintiffs admit that “[t]he course itself did not tell the
controller how to control aircraft, but rather was directed at what
can be described as general facility administration.”
Nos. 04-2877, et al.                                       13

  While the parties debate the details of the six-month ex-
perience requirement and whether it was waived, there is a
more fundamental problem with the plaintiffs’ negligence
claims. The contract between the United States and Midwest
required Midwest to staff the control tower with trained and
qualified controllers, and it was Midwest’s obligation to do
so, not the United States’. The district court recognized this
fact in granting the United States partial summary judgment
on claims premised on negligent oversight or training.
  The discretionary function exception to the FTCA pro-
vides that no liability shall lie for claims “based upon the
exercise or performance or the failure to exercise or perform
a discretionary function or duty on the part of a federal
agency or an employee of the Government, whether or not
the discretion involved be abused.” 28 U.S.C. § 2680(a).
Whether the discretionary function exception bars suit
against the United States depends upon two factors. See
Berkovitz by Berkovitz v. United States, 

, 536
(1988). First, whether the government employees violated a
specific mandatory statute, regulation, or policy, and sec-
ond, whether the conduct involved was the type of conduct
that Congress intended to shield from liability. 

This latter factor highlights that only governmental actions
based upon considerations of public policy are exempt. 

  Here, Congress authorized the FAA to enter into contracts,
as necessary, to carry out the functions of the FAA, and thus
the government did not violate a specific mandatory statute,
regulation or policy in hiring Midwest to provide training
and oversight at Meigs. The plaintiffs also fail to identify
any mandatory statute or regulation dictating how the FAA
must oversee private contractors or assure the contractor
complies with federal regulations and the contract provi-
sions. Where the plaintiffs’ claim is premised on negligent
14                                        Nos. 04-2877, et al.

oversight, such a showing is imperative. See, e.g., Kirchmann
v. United States, 

, 1276 (8th Cir. 1993) (holding
that the federal regulatory provisions relied upon by the
plaintiffs in their FTCA claim did not implicate a mandatory
statute because “each regulation governs operations where
the Air Force itself, rather than a contractor” performed the
specific operation).
   Because the plaintiffs failed to establish that the govern-
ment violated a mandatory statute, regulation or policy, we
next consider whether the decision at issue is one Congress
intended to protect from liability. In this case, the govern-
ment’s decision to contract out air traffic control services
was based on budgetary concerns, as well as a desire to
reopen smaller air traffic control locations—both of which
are clearly policy decisions. Thus, the discretionary function
exemption protects the government from liability for claims
premised on the lack of training, oversight, or qualifications
of air traffic controllers, since the government acted within
its discretion to contract those responsibilities out to
Midwest. Cf. United States v. S.A. Empresa de Viacao Aerea Rio
Grandense (Varig Airlines), 

(1984) (holding that
“actions against the FAA for its alleged negligence
in certificating aircraft for use in commercial aviation are
barred by the discretionary function exception of the
Federal Tort Claims Act,” 

because the FAA’s de-
cisions as to the manner of enforcing regulations is plainly
a discretionary activity, 

(holding that claims by a farmer and his family
against the United States under the FTCA based on ground-
water contamination caused during construction of a nearby
missile site were barred because any negligence of the
government in supervising the contractors’ employees was
protected under the discretionary function exception to the
FTCA). The plaintiffs’ remaining claims seek to hold the
Nos. 04-2877, et al.                                       15

United States liable for alleged negligence in the training
and staffing of Meigs. These are responsibilities for which
the United States, in its discretion, decided to contract to
Midwest. As a result, these claims are bared by the discre-
tionary function exemption. Accordingly, the district court
properly granted the United States summary judgment on
these claims.
   Finally, the plaintiffs argue that the district court erred
in denying their motion for leave to file an amended com-
plaint. The plaintiffs had requested leave to file an amended
complaint after the district court granted the defendants
partial summary judgment. The district court denied this
motion, finding that all but one issue raised in the proposed
amended complaint had been disposed of by the partial
summary judgment ruling. The one new issue alleged the
United States was negligent in failing to install radar equip-
ment at Meigs. The plaintiffs do not assert this theory on
appeal. Rather, they maintain that the district court should
have allowed them to amend their complaint to include
specific allegations about FAA orders which governed the
conduct of FAA controllers. However, as the district court
concluded, allowing such an amendment would be futile
because the court had already considered the claimed
violations of FAA orders in the context of the previous
complaint. Moreover, the district court concluded that even
if the amendment were not futile, it would nonetheless deny
the motion because it would be unduly prejudicial to the
United States. Given that the plaintiffs’ motion came ap-
proximately three years after the start of the litigation and
approximately eight months after the plaintiffs completed
discovery, the district court did not abuse its discretion in
denying the plaintiffs leave to amend their complaint. See
Perrian v. O’Grady, 

, 194 (7th Cir. 1992) (holding
that appellate court should overturn a district court’s denial
of a motion to amend a complaint only if the district court
has abused its discretion).
16                                           Nos. 04-2877, et al.

                             III.
   Paul Alinsky, Jeffrey Walker, Colleen Canty, Sheba Van
Pelt, Taiciana Phillips, Donetta Ladd, and Barbara Polka
died in a tragic accident. The United States, however, is not
liable for their deaths because it did not provide the al-
legedly negligent air traffic control services, and Midwest,
not the United States, was responsible for training and staf-
fing at Meigs. For these and the foregoing reasons, we
                                                        AFFIRM.

A true Copy:
       Teste:

                          _____________________________
                           Clerk of the United States Court of
                             Appeals for the Seventh Circuit




                    USCA-02-C-0072—7-13-05