1. The Problem: Squeeze-Through Fare Evasion
- Many London Underground barriers have a small gap at the outside edge of the swinging paddles where they are meant to meet in the middle
- Fare dodgers exploit this by pressing through the gap, which slightly flexes the paddles, widening the opening just enough to slip through. We see it on social media and in person when using the Tube.
- This is a design flaw combined with mechanical slack from wear and tear, not intentional functionality.
- TfL loses an estimated £130 million annually to fare evasion.
2. Why It Persists
- Technical feasibility: There’s no reason (at least theoretically) why the barriers cannot be modified to close the gap.
- Practical barriers: Existing discussions about cost or disruption focus on full barrier replacement, not simple paddle modifications. I have never read in the news media a discussion on making the barriers more effective in stopping fare dodgers who can push through easily. Far too easily.
- Current approach: TfL relies on a mix of enforcement, CCTV, and selective upgrades, rather than fixing the mechanical flaw network-wide. We now see, for instance, more security guards at the barriers at some stations.
3. Practical Modification Concept
Objective: Eliminate the ‘squeeze gap’ while keeping barriers fully operational. I am not staying that the whole barrier needs to be replaced. Changing the paddles and mechanisms that control the paddles would be sufficient if that is possible. This would be a ‘retro fit’ in modern repair parlance.
Proposed modification:
- Extend paddle length or add overlapping edges
- Each paddle would slightly overlap the neighboring edge when fully closed, eliminating any exploitable gap.
- Better materials or reinforced edges could prevent bending under pressure.
- Reinforce the pivot mechanism
- Slightly stronger hinges or torque-resistant pivots to handle extra leverage from extended paddles.
- Phased implementation
- Work done at night or during weekend closures.
- Start with stations with highest fare evasion rates, then scale across the network.
- Sensor & safety compatibility
- No changes needed to contactless card readers or optical sensors, as they detect passage independently of the paddle gap.
4. Rough Cost Analysis
Assumptions:
- ~270 Underground stations.
- Only modifying existing barriers, not replacing them.
- Estimated retrofitting cost per barrier: £2,000–£5,000 (materials + labor).
- Average 4–6 barriers per station.
Network-wide cost estimate:
- Barriers: 270 stations × 5 barriers × £3,500 average = ~£4.7 million total.
- Implementation: Night/weekend labor and minimal supervision: £1–2 million.
- Total retrofit cost: ~£6–7 million. You could quadruple this if you like and the maths still add up.
Comparison to annual losses:
- £130 million lost to fare evasion per year.
- Even a 50% reduction would recover £65 million annually.
- Payback period: Less than 2 months, a fraction of the full replacement cost (£270+ million).
5. Conclusion
- The squeeze-through problem is primarily a mechanical/design flaw, not an unavoidable limitation.
- A simple retrofit of paddle edges is technically feasible, inexpensive, and could pay for itself extremely quickly.
- The main reason it hasn’t been implemented is bureaucracy, inertia, or prioritization of more complex projects, rather than engineering impossibility.
Why don’t we hear TFL talking about upgrading the barriers? They are clearly defective if Joe Blogs can force through them AT WILL. It is easy. Really easy. Surely TFL has gone into this in some detail and if so, why don’t we hear an announcement? Or perhaps there has been one!?
More: human behavior
