IFR Fuel Requirements in Canada: What CARS 602.88 Actually Says

Fuel questions on the INRAT are straightforward once you know the rule — but a surprising number of candidates confuse the Canadian requirement with what they've read on American aviation sites. CARS 602.88 is the regulation. Here's exactly what it says and how to apply it on exam questions.

The basic IFR fuel requirement under CARS 602.88

Under CARS 602.88, before departing on an IFR flight you must carry enough fuel to:

The 45-minute reserve is calculated at normal cruising fuel consumption — not best economy, not maximum endurance. It gets added on top of everything else. This is the part candidates most often get wrong: they calculate fuel to destination plus alternate and forget the reserve sits on top of that total.

When do you need an alternate?

The alternate requirement comes from CARS 602.122. You must designate an alternate aerodrome when the weather at your destination is forecast to be below certain minima during the period from one hour before to one hour after your estimated time of arrival.

The threshold: if the ceiling is forecast below 1,000 feet above the lowest applicable instrument approach minimum, or visibility below 3 statute miles, you need an alternate. This is Canada's version of what American pilots call the "1-2-3 rule" — the numbers are different, so don't carry that over.

If no alternate is required (destination weather is forecast above those minima), your fuel requirement drops to: fuel to destination plus 45 minutes. Simpler, but the 45-minute reserve still applies.

What qualifies as an alternate aerodrome?

An aerodrome qualifies as your IFR alternate if it has a usable instrument approach and is forecast to be at or above alternate minima at your ETA. Alternate minima in Canada are published on approach plates or in the Canada Flight Supplement. If no alternate minima are published for an airport, standard alternate minima apply: 600-2 for precision approaches, 800-2 for non-precision.

You can't just pick the closest airport — it has to actually be usable when you need it. Candidates sometimes designate alternates without checking whether the forecast weather at the alternate meets alternate minima. That's a scenario the INRAT will test.

A worked fuel calculation

Say you're flying IFR from CYYZ to CYWG. Weather at CYWG is forecast below alternate minima at your ETA, so you designate CYQR as your alternate. Your flight planning shows:

• CYYZ to CYWG: 2 hours 15 minutes at cruise fuel flow of 40 L/hr = 90 L
• CYWG to CYQR: 45 minutes at 40 L/hr = 30 L
• 45-minute reserve at 40 L/hr = 30 L
• Minimum fuel required: 150 L

If you only loaded 130 L thinking the alternate fuel was your reserve, you'd be 20 L short of the legal minimum. That's the trap. On the exam, read the question carefully — they'll give you a scenario and ask whether the fuel load is sufficient under CARS 602.88.

How this differs from the FAA requirement

American IFR fuel rules (FAR 91.167) use the same basic structure: destination + alternate + 45 minutes. The math is nearly identical. Where Canadian candidates who have also studied FAA material sometimes get confused is on the alternate threshold — the 1-2-3 rule in the US (1 hour window, 2,000 ft ceiling, 3 SM vis) is different from Canada's CARS 602.122 criteria. The fuel formula is the same; the trigger for needing an alternate is different.

The INRAT tests Canadian regulations. Always default to CARS, not FARs, when you're on this exam. For the full picture of how fuel requirements fit into IFR flight planning — including when a flight plan is required, required fields, and closing procedures — see the IFR flight plan requirements guide.