Obsah

Bristol Blenheim Mk IV

STARTING

TAKE OFF

Take Off can be performed at +5Lbs Boost or +9 Lbs Boost with boost cut out Enabled.

It is recommended that boost Cut Out is used for takeoff. In Real life a +5Lbs Boost take off was performed with Cowl Flaps closed. A +9Lbs take off with Cowl Flaps 1/4 Open. For ALL take offs in the TF Blenheim Cowl Flaps should be set to 1/4 Open.

CLIMB

Cruise

Combat Concessions (5 Min)

Descent

Long Cruise descents from high altitude at Idle power with cowl Flaps closed can result in approaching Min CHT of 100C. If this happens advance Boost slightly as required to ensure CHT is kept above 100C

LANDING

WARNING High Rates of Descent at <85MPH IAS can result in running out of elevator authority in the flare.

GROUND OPERATION

LIMITATIONS Temps
Min CHT 100C
Max CHT 235C
Min Oil Temp 40C
Max Oil Temp 85C

FUEL SYSTEM

The Blenheim has 4 fuel tanks. 2 Tanks in each wing referred to as Inner and Outer tanks. Fuel quantity gauges are located above the pilots left shoulder. Two gauges are present to indicate the fuel remaining in both Port and Starboard tanks. Each wing has two tanks Inner and Outer. To read a specific tank Fuel Quantity first select the desired tank using the the rotary switches.

BOMB AIMERS STATION

The Bomb aimers station has a number of player controls. Two Yellow Manual Bomb release buttons are located on the Chart table.

A total of 4 switches are located on the forward instrument panel. These Mode switches allow the bomb aimer to select Bomb delivery modes.

Course Setting Bombsight Operation.

The Blenheim MKIV is equipped with the Course setting Bomb sight. This is a simple vector sight that provides an aiming reference for bomb release. The Bomb aimer inputs Bomb release HEIGHT and GROUND SPEED and drift. It is important to understand that the Bomb aimer must input Bomb Release HEIGHT not Altitude. Bomb Release Height = Altitude – Target Elevation. In addition the Bomb Aimer must determine the GROUND SPEED and input this to the sight. So the Bomb aimer needs to first determine TAS then apply the wind to determine the ground speed. In Nil wind conditions TAS = GROUND SPEED.

The Sight consists of a vertical post which combines as the Height scale and back sight. The back sight consists of an aperture with the Tgt Height Ref index pin on the right and left sides. A scale on the vertical arm shows the current Height set by the bomb aimer.

The sight also has a horizontal arm with attached Track reference wires. The Horizontal arm also has the foresight which consists of the Ground Speed Ref index pin. The horizontal arm has two ground speed scales. The White scale on the left (not visible with zero drift) has a mph scale. The Red scale on the right is also a Ground Speed scale but in “Minutes to fly 60 miles”. This is easily visible in most situations.

In the graphic below The Release Height is set to 7000ft. The ground Speed is set to 12Min to cover 60 miles i.e. 5 miles per minute or 300mph Ground Speed. To obtain the correct aiming reference the Bomb Aimer moves his Eye line to line up both the Ground Speed ref pin and the Release Height ref pin….i.e. Like with a Rifle he aligns the backsight with the foresight. In the Sim in bombsight view the eyeline is automatically set for you. With these Ref pins aligned the bomb aimers eyeline is now on the correct release angle sight line.

With these settings the aircraft is then flown so the target passes through either the Left Aiming aperture or the right aiming aperture. (In the sim it needs to be the right aiming aperture)The Bombs are manually released as the target passes through and adjacent to the ref pins.

In Drift situations the Bomb aimer lays of the drift so that ground features are tracking directly parallel to to the horizontal arm and its drift wire reference lines. The aircraft is then flown to ensure the target tracks down the Drift wire guideline to the aiming aperture.

Red Minutes to fly 60 miles to Miles per Min and MPH.

Tip

In the Sim you can simply use the digital values of release height and ground speed to set the sight accurately rather than refer to the respective scales.

BOMB BAY DOORS

These are Automatic. the Doors are held close by Bungee operation. The weight of the falling bomb will open the doors which will then snap shut after bomb release.

Air Intake Heat Control

Required ON for all operations in cloud or if rough running occurs for no obvious reason.

Mixture Control

In CLOD there is little value in running mixture in any other setting than AUTO RICH „NORMAL“, Fully to the rear. In NORMAL you will get automatic Altitude compensation on the Rich schedule. If you have a real need to minimise fuel Burn then mixture can be set to AUTO LEAN „WEAK“ which is fully forward. In WEAK (AUTO LEAN) you will also get altitude compensation but on the Weak schedule. IRL there were Boost limits in WEAK, these have not yet been tuned in TF V1.0