How to fly a half cuban eight

The half Cuban-Eight combines a loop element, a 45° line and a half roll. It is a nice aerobatic figure and regularly features in Club, Sportsman and Intermediate level competitions as well as in later levels, though there tend to be several additional embellishments at Advanced and Unlimited. Whilst relatively straight forward, there are several key training points that differentiate those who fly it well and those that don’t.

Judging Criteria
  • A constant radius looping element
  • The looping element clearly stops when the aircraft reaches 45° down (inverted) to mark the end of the loop radius – at 5/8 of the circle
  • 45° inverted down line (ZLA not CGT)
  • Half roll (CGT) centred on the two 45° down lines – a moderate degree of yaw or pitching is acceptable as per CGT rules but ‘barrelling’ or sinking away from the projected 45° line is penalised
  • 45° down (ZLA) – has to be the same length as the inverted 45° line so the the roll is centred exactly
  • 3/8 loop back to horizontal matching the same radius as the first 5/8 loop – exit does not have to be the same height as entry but has to be in straight and level flight (CGT)

How to Fly a Half Cuban Eight

8.5.6.1
9.1.4.2

In this example I will assume that the HASELL checks have been completed and height and speed is sufficient and it is trimmed to 0 G.

  • Fly the first 5/8 of a loop as per the ‘How to Fly a Loop‘ blog post
  • Looking at the wing sight, stop the loop at 45° down (inverted)
  • Count “1 banana, 2 banana”
  • Looking at the wing sight, apply full aileron until the 45° down (canopy up) reaches the horizon – this insures a perfect half roll and gets you to maintain the 45° line. Another technique is to look forward during the roll. This is ok but care must be taken to immediately move the eyes back to the wing sight so that any errors are immediately corrected.
  • Still looking at the wing sight making sure you maintain 45° down line, count “1 banana!
  • Pull to the horizontal
How to Fly a Reverse Half Cuban Eight

8.5.2.1
9.1.2.2

  • Looking at the wing sight, pull to 45° up
  • Count “1 banana”
  • Looking at the wing sight, apply full aileron deflection until the 45° up line (inverted) reaches the horizon
  • Count “1 banana, 2 banana”
  • Still looking at the wing sight, apply elevator, drawing a constant radius loop until upright and straight and level – a ‘harder’ pull when flying faster as per ‘How to Fly a Loop’ blog post

Common Mistakes
  • 45° lines being too shallow or too steep
  • Rolling off heading
  • Lines before and after the rolls being different lengths

The judging criteria has been taken from CIVA Section 6 part 1 PDF from the CIVA website.

Flying a good half-Cuban takes practice. Learning the correct technique will save you hours of fruitless practice.