UK Class 1 Carrier-Deck


Version 1.5         February 2017





Applicability of Generic Rules


The generic British Model Flying Association (BMFA) rules for Control Line flying are in force for UK Carrier-Deck events

The Link Page on this site contains a hyperlink to this information on the BMFA Website

Carrier Deck 


Visit this site’s Carrier Deck Specification page for details


Aircraft Requirements



Models must have a fixed or retractable landing gear. If a retractable gear is used, it must be lowered for landing.   



The model must be equipped with an arresting hook which when extended may not be longer than a one-third (1/3) the length of the fuselage.



The model wingspan shall be 44 inches maximum

This rule has been suspended for UK carrier-deck flying – there is no restriction on wingspan


It is permissible to change the position of any control surface during flight

This rule allows the use of moveable flaps, ailerons, rudder, dive brakes,
spoilers etc

2017 Addendum: to clarify and legitimise the widespread use of R/C throttle control: Any function EXCEPT elevator control may be activated by a) radio control b) electrical signals transmitted along the control lines c)  mechanical means (e.g. Brodak three-line bellcrank; however, control of the elevators MUST be achieved solely and directly using the pilot’s handle, control lines and in-aircraft bellcrank or equivalent mechanical means


The model shall be rigged for counter-clockwise flight



Models shall not exceed four (4) pounds (1.8kg) weight in flight
configuration, but without fuel



A safety strap must be used between the pilot’s wrist and the control handle
throughout the duration of each flight

This is a new UK rule to bring Class 1 flying into line with most other high-speed C/L disciplines


Engines used must be either

a)  Reciprocating: engines are limited to a displacement of  .4028 cubic inch maximum

b) Electric

c) Jet

a) The US displacement of .4028 c.i. equates nominally to 6.5cc

      b) There is no restriction on electric motor size or power

         c) There is no restriction on jet engine size or power



Twin-reciprocating-engined models may use two .21 engines even though this combination exceeds the .4028 limit

This is a rule specifically for UK carrier-deck flying –.21 ci equates nominally to 3.5cc


The model must have an effective silencer

“Silencer effectiveness” for the UK is defined in the BMFA rulebook in terms of  decibels measured at various positions around the aircraft with a meter. Local flying-site rules may require much lower noise levels than this – always check with the event organiser


Tuned pipe systems of any form are banned

This rule has been suspended for UK carrier-deck flying – tuned pipes are permitted

Control Line Requirements


Minimum Line Sizes: These are determined by the number of lines which bear the load of the model in flight.  A load bearing line is one which is tight during the pull test as determined by visual inspection, line plucking, or other means.  Non-load bearing lines (lines which are not tight during pull test) may be any



Line Pull Test: The lines shall be subjected to a pull test of 25G (25 times the weight of the model)


Single-Strand Minimum Line Diameters:

One Line:       .029 inches (0.737mm)

Two Lines:     .020 inches (0.508mm)

Three Lines:  .015 inches (0.381mm)



Multi-Stranded Minimum Line Diameters:

Two Lines:      .020 inches (0.737mm)

Three Lines:   .015 inches (0.381mm)



Control Line Length: Lines shall be between 60 and 60½ feet (18.3 to 18.44 metres) long measured from the bellcrank pivot to the handle attachment points



Control Line Position: Al lines shall emerge from the model within the fore-and-aft range covered by the wing root chord.  All lines other than the elevation control line(s) shall emerge either between the elevation control lines or, if not between, then within one (1) inch of the nearest elevation control line.


Official Flight


A flight is official when the aircraft crosses the stern of the deck as the contestant signals for the timed low speed run.




Three (3) attempts will be allowed for two (2) official flights.  Any of the following shall constitute an attempt:



Failure of the contestant’s model to become airborne within five (5) minutes
of being called to the deck



Any endeavour to make a takeoff



Whipping or shortening the effective length of the control line(s) during
high speed flight



Exceeding an altitude of 20 feet for more than one half (1/2) lap during
high speed flight



Flight terminated for any reason prior to the signal for low speed flight


Flight Termination


Any of the following shall result in the immediate termination of the flight:



Touching the ground or any obstruction by any part of the model



Touching the protective ramp by any part of the model



Touching the deck with any part of the model except during initial takeoff
and during landing approaches following the signal for landing



The model does not maintain forward counter-clockwise motion with respect to the ground


Points for the model


Bonus points: will be awarded to a scale model of a carrier aircraft of any nation, provided it displays the national markings of the using nation. A carrier aircraft is any man-carrying aircraft which was successfully flown and which meets at least one (1) of the following requirements:



The aircraft made an actual carrier-type takeoff and arrested landing on an
actual or simulated carrier deck

Documentary evidence (e.g. 3-views, photos) will be required


The aircraft is designated as a carrier aircraft by an acceptable source (in
cases where actual carrier-type takeoff and arrested landing are not

The acceptability of a data source is at the discretion of the Contest Director


Adherence to Scale Dimensions: Scale 3-view drawings of the full-scale aircraft and proof that the aircraft meets the above requirements must be submitted to be eligible for scale bonus points. Class I models will receive 100 bonus points if the linear dimensions of the major components of the model are to the same scale, within plus or minus five (5) percent tolerance.  Models which appear to comply with this tolerance upon rudimentary inspection need not be further checked except in case of dispute. 

Judges’ Guide: “Major components” are considered to be the fuselage (excluding surface markings) and air brakes, the side view profiles of the vertical stabiliser and rudder, the top view profiles of the wing and horizontal tail surfaces, and all movable surfaces which are attached to or form part of these surfaces (flaps, ailerons, elevators, etc)


Moveable surfaces: Although complex motions of movable surfaces need not be duplicated (such as Fowler flaps), the general direction of movement must be the same as on the full-scale aircraft being modelled.  Unless proven otherwise, ailerons shall be assumed to move simultaneously in opposite directions.  Although landing gear need not be to scale, it must emerge from model in the same location as prototype



Mechanical Protrusions:
If the engine or accessories protrude from the scale contours of the model, there may be openings in the skin sufficient to accommodate the protruding part with 1/4 inch (6mm) maximum clearance at all points round the protruding part



Dihedral: The model dihedral as viewed from the front must be similar (within two (2) or three (3) degrees by official’s visual judgement) to the actual  a eroplane as shown in the three-view drawing.  Namely, it must have some positive or negative angle, as shown on the three-view drawing.



Colour Scheme: The colour of the model must be similar to any military type aircraft paint scheme



Cockpit Canopy: If a clear canopy is not used the cockpit or canopy area must be defined with a contrasting colour or colour outline denoting the scale area



Multiple Engines: Five (5) points shall be awarded for each engine above one (1) used to power the model, providing such engines contribute to the performance of the model from takeoff through at least the high speed phase of the flight

Judges’ Guide: at completion of high speed timing, count number of engines running, subtract one (1), and multiply times five (5)




Rules for the Four Phases of the flight



Takeoff:  The model must successfully take off from free roll portion of deck.  At the time of release, the nose of the model must be no more than 42 inches (1.07metres) from the last arresting line.



High Speed Flight: The first seven (7) laps after takeoff constitute the high speed phase of the event.  Timing will start the instant the model is released for takeoff, and shall end when the model completes its seventh lap over the stern of the carrier. All high speeds will be calculated to the nearest 0.1mph. 



Low Speed Flight: When the contestant has decelerated the speed of his model to his satisfaction, he will signal the judges to start timing his low speed run by using a prearranged  signal that is acceptable to the judges.  This signal shall be given as the model crosses the stern of the deck, one (1) lap prior to the start of the low speed timing. The model will then be timed for seven (7) laps, using the stern of the carrier flight deck as the starting point. The start of the low speed run must be signalled for within three (3) minutes of the completion of the high speed run.  Time for the seven (7) laps shall be used to calculate the average speed.



Landing: All landings on the carrier deck shall be made at low speed only.  The landing must be signaled within three (3) minutes of completion of the low speed run.  After lining up with the deck upon completion of the low speed run, the pilot shall signal the judges that he is ready to land.  The signal of the pilot’s intent to land shall be given as the model crosses the deck beginning his lap prior to landing.  If other than a hand signal is used,
the pilot shall describe his signal to the official immediately prior to
each of his flights (i.e., before he starts his engine).



Arrested Landing Definition: An arrested landing is any landing in which the model’s forward motion is stopped primarily by the arresting hook engaging any arresting cable.  The landing is scored at the point where the model’s forward motion is first arrested, and the flight is terminated at that time. 


Judges’ guide: A model which is arrested in a normal attitude will receive full points.  If the hook subsequently becomes disengaged, or the model rolls or is  pulled off the deck after forward motion has been arrested, the landing score is  ot affected.  A model which stops on its nose and subsequently falls back into a  normal attitude will receive 50 points for a landing other than a three-point  attitude.

Points for  the Flight


High Speed Points: High speed points shall be scored the same as speed in mph, and to the nearest 0.1 mph



Low Speed Points: Low speed points will be scored as 10 times the ratio of high speed to low speed (10 x high speed divided by low speed).  The score will be calculated to the nearest 1/10 point. 

Low Speed Penalties: No low speed points will be awarded if any of the following infractions occur:

1) the flight radius of the model is lengthened by the contestant walking in a circle greater than three (3) feet in diameter. 

2) The model exceeds a 60 degree nose-high attitude except for momentary inadvertent deviations.  When the 60 degree limit is exceeded, the contestant will be notified immediately and must correct model attitude immediately. Failure to do so will result in loss of low speed score.  A maximum of three notifications will be given. 

Judges’ Guide: High speed divided by low speed is the same as low speed flight  time divided by high speed flight time.



The contestant may step out of the three-foot circle to regain control of the  model when lines go slack, but he is expected to return to the three-foot circle  when control is established.

The fourth notification shall result in loss of the low speed points.


Multiple Engine Scoring: Models powered by two (2) or more engines must keep all engines running through low speed phase of flight to garner full points for speed differential. Failure to do so will score only half of the potential low
speed points



Landing Points: Landing (dead stick included) shall be scored as follows:



Arrested landing with plane in normal three-point attitude (takeoff attitude), 100 points



Arrested landing with plane in other than normal three-point attitude, 50 points



Arrested landing with plane coming to rest on its back or with one (1) wheel off the edge of the deck, 25 points



All other landings, zero (0) points



Landing Penalties: From the above score, five (5) points will be deducted for each unsuccessful landing approach made after signalling.  Each lap flown after signalling shall be considered a landing approach even if the contestant does not attempt a landing. The landing score will, in no instance, be less than zero (0).




Competition scoring shall be based upon the contestant’s best official flight score. The score of an official flight shall be the sum of the high speed points, the low speed points, the landing points, and the bonus points (if applicable).  If the flight is terminated after the low speed signal (see section 9.3), the score shall be bonus points (if applicable) plus points for all phases of flight completed prior to the termination.


“Builder of the Model Rule”


The “Builder-of-the-Model” rule does not apply to the CL Navy Carrier events

Use of a model not built by the flyer is permitted

Restrictions on the use of engines and models


Once a model or engine has been used by a contestant to make an official
attempt in an event, the same model or engine cannot be used by another
contestant in that contest.

This rule has been suspended for UK carrier-deck flying

Timing apparatus


Stopwatches with graduations of 1/10 second or finer shall be used for timing all UK  Carrier events.


Flying to set a Record


The standard BMFA regulations will apply – see the BMFA Rulebook

See the BMFA Website