radar in the Su-57. The Su-35 features the
N135 Irbis passive electronically scanned
array (PESA) radar. The weapon suite of
both ghters is virtually the same.
In fact, the Su-35’s development ran
alongside that of the Su-57. The new
Lyulka AL-41F1 engine, a thoroughly
upgraded version of the AL-31F, was
adopted for both ghters. The only
di erence is that the AL-41F1S (izdeliye
117S) of the Su-35 has its own control
system, while control of the AL-41F1
(117) in the Su-57 comes via the aircraft’s
ight control system. The AL-41F-1S has a
maximum dry thrust of 86.3kN (19,401lb
st), afterburning thrust of 137.3kN
(30,865lb st), and emergency thrust of
142.2kN (31,967lb st). Provision was made
for 11,500kg (25,353lb) of internal fuel
in the Su-35, 22 per cent more than in
the Su-27.
The ‘brains’ of the Su-35 are integrated
within the KPrNO-35 (Kompleks Pritselno-
Navigatsionnogo Oborudowaniya,
targeting-navigation equipment
complex; KPrNO-35S for the VKS variant),
controlled via a central computing system
incorporating two Baget-53 computers.The Sukhoi Design Bureau is responsible
for the systems integration, which is a
novelty because in the past re control
and ight-navigation systems were
integrated by instrument companies,
usually by RPKB of Ramenskoye on Sukhoi
ghters. A similar Sukhoi-led approach
was retained for the Su-57.
In the cockpit, the pilot has a pair of 15in
MFI-35 multi-function displays (MFDs)
and a KAI-35 head-up display (HUD),
all supplied by RPKB. A smaller RPKB
MFPI-35M control panel by the pilot’s
left knee is used to present secondary
information such as weapons states,
engine data and aircraft systems. A small
panel under the HUD presents targeting
and navigation data.
Typically for a Russian ghter, a Su-35
pilot has three air-to-air targeting sensors:
the radar, an infra-red search and track
(IRST) and a helmet-mounted sight
(HMS). The N135 radar — developed by
the Tikhomirov NIIP institute — is part
of the Sh135 Irbis (Snow Leopard; Irbis-E
for export) system that includes the
Khibiny-M electronic countermeasures
suite and IFF (identi cation friend orChinese equipment and weapons are
integrated. The few images of PLAAF
Su-35s reveal that externally they only
di er from the Russian variant in minor
changes in the antennas.
Other trade could come from the UAE,
with realistic estimations for between
12 and 24 aircraft. Indonesia plans a
smaller number — 11 ghters — and
this past summer it was announced
that the purchase had been approved
by the Indonesian government. Other
potential customers, such as Libya and
Venezuela, have fallen by the wayside.
Libya’s ambitions for 12 Su-35s were at
a very advanced state in 2009, but the
subsequent unrest in the country has
halted any such potential.How good is the Su-35?
The Russian deputy minister of defense
Yuri Borisov told Russian television in
August 2017, ‘In the Syrian campaign the
Su-35 received the best marks’. Roughly
translated, his comments added, ‘It is not
inferior even to the rst-stage Su-57’. In
fact, the biggest di erence between the
Su-35 and Su-57 is the airframe, which in
the latter is designed for sustained ight
and maneuvering at supersonic speed,
with internal weapons carriage to help
facilitate a smaller radar cross-section.
Both aircraft are produced at the same
production facility, with the same tooling,
so production standards will be similar.
The engines of both ghters are virtually
the same. Only the upgraded Su-57 with
new-generation ‘izdeliye 30’ engines
will be signi cantly improved. These
engines could easily be imported into
the Su-35. The main di erence in terms of
war ghting avionics is the N036 Byelka
active electronically scanned array (AESA)Top: Su-35Ss
of the Sokoly
Rossii (Falcons
of Russia) team
from the combat
training center at
Lipetsk.
Right: Twin
braking
parachutes billow
in the exhaust
effl ux as this
Su-35S taxies in
post-mission.FIGHTER FOCUS // Su-35
74 February 2018 //^ http://www.combataircraft.net
70-77 Su-35 C.indd 74 14/12/2017 11:17