Project management

Why this matters

Many graduates of this programme will be more than pilots or technicians: they will set up drone service units, submit project proposals to agencies or start businesses of their own. Most failed drone projects fail not because of the technology but because the scope was vague, the schedule was unrealistic, or nobody knew which work could not slip. This course follows one hypothetical case through all five modules: setting up a drone survey service unit for a municipality. Every number is made up for practice, not real prices or data.

What a project is

A project is temporary work that creates a unique result, with a clear start and end. It differs from operations, which repeat continuously. Setting up the survey unit is a project; the weekly survey flights after it is running are operations.

There are two main references. The PMBOK Guide from the Project Management Institute (PMI), whose 8th edition was published in November 2025, organises knowledge into six principles and seven performance domains and brings process guidance back. ISO 21502:2020 is ISO’s guidance on project management.

Project charter and WBS

A project charter authorises a project to start. It states the goal, scope, deliverables, sponsor, project manager, rough budget, main risks and success criteria. The drone knowledge hub’s unit on project governance and monitoring stresses naming the work owner, approver, reviewer and data users in this document from the start.

A work breakdown structure (WBS) breaks large deliverables into manageable pieces in a hierarchy. The lowest-level pieces (work packages) must be small enough to estimate in time and cost and to assign to a single owner.

A WBS is organised by deliverable, not by department or by time, and must cover all the work in scope. Work that is not in the WBS is out of scope.

The critical path

The Critical Path Method (CPM), published by Kelley and Walker in 1959, finds the work that cannot slip at all. It uses two passes. The forward pass finds the earliest start (ES) and earliest finish (EF); the backward pass finds the latest start (LS) and latest finish (LF). The difference LS − ES is the float. Tasks with zero float are on the critical path: if they slip, the whole project slips.

tasks = {
    "A": ("permits and registration", 4, []),
    "B": ("procure drones and equipment", 6, []),
    "C": ("train pilots", 3, ["A"]),
    "D": ("set up data system", 2, ["B"]),
    "E": ("test flights", 2, ["B", "C"]),
    "F": ("operations manual", 1, ["C"]),
    "G": ("pilot service", 3, ["D", "E", "F"]),
}
es, ef = {}, {}
for key, (name, weeks, pred) in tasks.items():
    es[key] = max((ef[p] for p in pred), default=0)
    ef[key] = es[key] + weeks
finish = max(ef.values())
ls, lf = {}, {}
for key in reversed(list(tasks)):
    successors = [k for k, (_, _, pred) in tasks.items() if key in pred]
    lf[key] = min((ls[s] for s in successors), default=finish)
    ls[key] = lf[key] - tasks[key][1]

print("task  ES  EF  LS  LF  float")
for key in tasks:
    print(f"  {key}   {es[key]:>2}  {ef[key]:>2}  {ls[key]:>2}  {lf[key]:>2}  {ls[key] - es[key]:>4}")
print("project duration:", finish, "weeks   critical path:", " -> ".join(k for k in tasks if ls[k] == es[k]))

task  ES  EF  LS  LF  float
  A    0   4   0   4     0
  B    0   6   1   7     1
  C    4   7   4   7     0
  D    6   8   7   9     1
  E    7   9   7   9     0
  F    7   8   8   9     1
  G    9  12   9  12     0
project duration: 12 weeks   critical path: A -> C -> E -> G

The tasks in the code are ordered so that predecessors always come first, which the forward pass needs.

The project takes 12 weeks, and the critical path is permits, pilot training, test flights and pilot service. If permits slip one week, the project slips one week at once, but procurement can slip a week without moving the end date. The project manager should therefore push permits before procurement, even though procurement takes longer.

o, m, p = 4, 6, 11
expected = (o + 4 * m + p) / 6
sd = (p - o) / 6
print(f"expected {expected:.2f} weeks   standard deviation about {sd:.2f} weeks")
print(f"float of task B is only {ls['B'] - es['B']} week, so B could become critical")

expected 6.50 weeks   standard deviation about 1.17 weeks
float of task B is only 1 week, so B could become critical

Agile and Scrum

Parts of the work whose needs are unclear, such as a dashboard showing survey results to the municipality, suit an agile approach. The Agile Manifesto (2001) values individuals and interactions over processes and tools, working software over comprehensive documentation, customer collaboration over contract negotiation, and responding to change over following a plan.

Scrum, as defined in the 2020 Scrum Guide, is the most widely used agile framework. It has:

• Three accountabilities: Product Owner, Scrum Master and Developers
• Five events: the Sprint (a cycle of one month or less), Sprint Planning, Daily Scrum, Sprint Review and Sprint Retrospective
• Three artifacts: Product Backlog, Sprint Backlog and Increment

Class activity

Common mistakes

Summary

• A project is temporary work with a unique result; choose predictive, agile or hybrid by how clear the requirements are
• The charter authorises and scopes the project; the WBS breaks deliverables into manageable pieces
• CPM finds the critical path and float; PERT uses three estimates for uncertain durations
• Scrum has three accountabilities, five events and three artifacts, suiting work whose needs can change

Check your understanding

1. Are the weekly survey flights after the unit is set up a project or operations?
2. A task has ES = 5, EF = 9 and LS = 7. What is its float?
3. A task has o = 2, m = 3 and p = 10 weeks. What is its PERT expected time?
4. If a critical-path task slips by 3 days, how late will the project be?
5. Who in Scrum is accountable for ordering the Product Backlog?