Here's the Technical Regs for those interested. 10.2.3 is the interesting one but it's how you interpret it.
ARTICLE 10 : SUSPENSION AND STEERING SYSTEMS
10.1 Sprung suspension :
10.1.1 Cars must be fitted with sprung suspension.
10.1.2 Any suspension system fitted to the front wheels must be so arranged that its response
results only from changes in load applied to the front wheels.
10.1.3 Any suspension system fitted to the rear wheels must be so arranged that its response
results only from changes in load applied to the rear wheels.
10.2 Suspension geometry :
10.2.1 With the steering wheel fixed, the position of each wheel centre and the orientation of its
rotation axis must be completely and uniquely defined by a function of its principally
vertical suspension travel, save only for the effects of reasonable compliance which does
not intentionally provide further degrees of freedom.
10.2.2 Any powered device which is capable of altering the configuration or affecting the
performance of any part of any suspension system is forbidden.
10.2.3 No adjustment may be made to any suspension system while the car is in motion.
10.3 Suspension members :
10.3.1 With the exception of minimal local changes of section for the passage of hydraulic brake lines,
electrical wiring and wheel tethers or the attachment of flexures, rod ends and spherical
bearings, the cross‐sections of each member of every suspension component, when taken
normal to a straight line between the inner and outer attachment points, must :
a) Intersect the straight line between the inner and outer attachment points, with the
exception of front suspension elements for the sole purpose of ensuring minimum
clearance with the wheel rim at full steering lock.
b) Have a major axis no greater than 100mm.
c) Have an aspect ratio no greater than 3.5:1.
d) Have no dimension which exceeds 100mm.
The major axis will be defined as the largest axis of symmetry of any such cross‐section. The
length of the intersection of this axis with the cross‐section must not be less than 95% of the
maximum dimension of the section.
10.3.2 Suspension members having shared attachment points will be considered by a virtual
dissection into discrete members.
10.3.3 No major axis of a cross section of a suspension member, taken normal to a straight line
between the inner and outer attachment points, when assessed in accordance with Article
10.3.1, may subtend an angle greater than 10° to the reference plane with the car set to the
nominal design ride height.
10.3.4 Non‐structural parts of suspension members are considered bodywork.
10.3.5 There may be no more than six suspension members connecting each suspension upright to
the fully sprung part of the car.
Redundant suspension members are not permitted.
10.3.6 In order to help prevent a wheel becoming separated in the event of all suspension members
connecting it to the car failing, flexible tethers each with a cross sectional area greater than
110mm² must be fitted. The sole purpose of the tethers is to prevent a wheel becoming
separated from the car, they should perform no other function.
Each wheel must be fitted with three tethers each of which comply with FIA standard 8864‐
2013 and each of which has a minimum energy absorption of 7kJ. No suspension member may
contain more than two tethers.
Each tether must have its own separate attachments at both ends, which :
a) Are able to withstand a tensile force of 70kN in any direction within a cone of 45°
(included angle) measured from the load line of the relevant suspension member.
b) Are able to accommodate tether end fittings with a minimum inside diameter of 15mm.
c) Do not share a common fastener and are designed such that the failure of one
attachment point will not lead to the direct failure of an adjacent attachment point.
Furthermore, at least two of the three tethers must have attachment points which:
d) On the survival cell or gearbox are separated by at least 100mm measured between the
centres of the two attachment points.
e) On each wheel/upright assembly are separated by at least 90° radially with respect to
the axis of the wheel and 100mm measured between the centres of the two attachment
points.
Each tether must exceed 450mm in length and must utilise end fittings which result in a tether
bend radius greater than 7.5mm.
Each team must supply detailed geometries which clearly show that any two of the three
tethers will independently prevent a wheel from making contact with a driver’s head during an
accident, assuming 7kJ energy absorption in each tether.
10.3.7 Once the suspension members are fully defined to satisfy Articles 10.3.1 to 10.3.6, it is
permissible to apply any geometry to the outside of the suspension members, provided that:
a) It is contained within either of the volumes defined by Article 11.4.1 (and outboard of a
plane that lies 5mm inboard of the inboard plane of the wheel rim) or Article 11.5 with
the steered wheels in the straight‐ahead position.
b) It is rigid and rigidly secured to the suspension members (rigidly secured means not
having any degree of freedom), with the exception of front suspension elements where
minimal flexible parts are allowed for the sole purpose of ensuring minimum clearance
with the wheel rim at full steering lock.
There is great vid of Senna driving one handed virtually all the way around Monaco, without power steering....which is now allowed.
