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ARM505

Tinmouse Panel, RL story, Part 2 - Take off and climb

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Here's my view of the sim, just prior to my turn. Apologies for the terrible quality, it's taken through the window, using an abysmal cellphone camera.http://img.photobucket.com/albums/v244/ARM505/Image038.jpg........gauges showing 'good to go', I called for Max Thrust.The Fleet Captain in the right hand seat, acting as 'dumb' copilot called 'Max Thrust set' after some tweaking of the levers under my right hand, and made the 80kts callout.We had been briefed that we weren't expected to know standard B732 operating procedures, and that we were to fly the aircraft using whatever procedures we were accustomed to - personally, I'm glad I had come from the B1900D. Although it is certified as a single crew aircraft, it is always operated using multi-crew procedures down here, so that was something I was at least used to, and despite the differences in aircraft, they used similiar callouts. Our emailed briefing instructions on the profile to be flown had also explained how the speed bugs on the airspeed indicator (ASI) were to be set - one bug at V1 (an 'action' speed, at which point the decision to continue the take off roll or stop on the runway must have been made, and action initiated), one bug at Vr (rotate speed, where the pitch up is initiated), the airspeed cursor at V2 (take off safety speed), and one final bug at V2+15kts (standard speed for initial climbout). We would be doing a Flap 1 take off.The simulator does a pretty good job of conveying the feelings during the take off roll. Whilst the visuals show that you're level, it obviously tilts backwards, giving you the feeling of being pressed slightly into your seat. One thing it doesn't do well however, is give a proper yawing feeling. It tries to tilt from side to side, but it's not quite convincing.Luckily, I managed to avoid testing its ability to imitate yaw, as I kept it relatively straight during the roll! Because we had been positioned ready to go, lined up on the runway, there had been no need to taxi, and therefore no need to use the tiller, which is only located on the Captains side of the aircraft. For directional control during the take off roll, the rudder only becomes effective above about 60 kts, and for this reason the nose wheel can be steered a tiny amount by the rudder pedals (5 degrees, as opposed to the 78 degrees or so allowed by the tiller). There's actually quite a bit of time between the 80 kts call and reaching V1, and I as the Pilot Flying (PF), just concentrated on keeping it straight. I trusted my 'dumb' copilot to call out any abnormalities, but it would have been really unfair of them to give me anything other than a normal take-off at this stage, and I knew that! (During the simulator training later, the piercing alarm of the fire bell would often make an unwelcome appearance round about this time!)In Microsoft Flight Sim, take off rolls can sometimes be likened to a pinball bouncing down a pipe, since in MSFS there's no way to stop your rudder pedals from operating the tiller! IRL, there is no way the tiller is touched during the take off roll, it's just way too sensitive at those speeds. Even the 5 degree nosewheel movement in either direction can be twitchy if you overuse it.Once reaching rotate speed (Vr), things start to happen relatively quickly. Here's where the time spent with the Tinmouse panel started paying off!'V1', called my F/OI removed my right hand promptly from the thrust levers and placed it on the yoke. From here on, it's 'GO', come what may.'Rotate!'.A brief pause to consider some factors at this precise moment. I was acutely aware that this was the first real 'moment of contact' between myself and the aircraft - in other words, this was my first true feel of actual aerodynamic control (barring the relatively dead feeling of small rudder corrections on the take off roll). I really didn't know precisely what to expect, other than what my friends had tried to prepare me for. You must understand that this was the first time I was operating an aircraft equipped with hydraulically actuated controls - no longer would I be able to feel the airflow over the control surfaces! I knew the theory behind it - aim to reach the target body attitude, about 15 degrees nose up or so initially, whilst rotating at 3 degrees per second, and note the increased effort required as the horizontal stabiliser enters ground effect during the rotation at about 10 degrees nose up. Don't do it too fast (it's uncomfortable for the pax, and more critically you risk striking the tail), and don't do it too slowly (which uses up excessive amounts of runway, and does not allow the aircraft to perform to it's certified standards regarding obstacle). So much for basic theory! But I had no real idea what it felt like.Now, back to myself at the controls - a few seconds later, I knew what it felt like! The simulator, being a computer, and therefore prone to overexaggerating mathematical theory, tends to overdo the feeling of the horizontal stabiliser entering ground effect. There was a definate pause at about 10 degrees nose up pitch, with a quite noticeable increase in the effort required to continue the rotation. In the real aircraft, there seems to be a smoother transition between the relatively light effort normally required to initiate rotation, and the slightly heavier pull required as the nose approaches 15 degrees. Some clarification here - the target attitude is initally about 15 degrees, but is then adjusted based on observed performance to maintain V2 (Take off safety speed) plus 15 kts. Company policy places a limit of 20 degrees body attitude while climbing out for passenger comfort however. At that time, I knew almost nothing of this though.To describe the force required on the yoke to rotate is difficult - it's all relative. But I will say that it's normally relatively light. MSFS falls somewhat short here, with many aircraft requiring quite a lot of stick deflection for the correct result. I would say the tinmouse aircraft also falls victim to this to a certain degree, but I want to try it out a little more, playing with the CoG and trim settings before I make up my mind. The aircraft is loaded such that the centre of Gravity (CoG) is obviously within limits, and this results in the aircraft almost being balanced on the main gear. Almost, but not quite of course! The correct stabiliser trim setting is calculated before take off, based on the CoG position which is calculated by the loading software as a %MAC, or percentage of the mean aerodynamic chord. This is then converted to a stabliser trim setting by the crew, using a table. In practice, it normally works out to around 5 units of stab trim, pretty much in the middle of the green band of the trim. These markings can clearly be seen on the Tinmouse thrust lever panel next to the right trim wheel.And so, I was away! The acting F/O called 'Positive rate of climb', which elicited my almost automatic call of 'Gear up'. The faint rumbling of the gear being retracted, with the associated faint thumping feelings played through my seat. 'Gear clean'.After the rumbling and rolling of the take off roll, things were now relatively smooth. My first impression was how smooth the controls were, a very nice feel - with one small exception, which was my next impression (you're going to laugh) it felt too 'pitchy', or sensitive in the pitch axis, just like many MSFS aircraft! I don't know what it is about pitch sensitivity in simulators, but rest assured it's not just limited to MSFS - the full motion deals experience it as well! Admittedly, the B732 simulators are quite old now, I'm sure the more modern examples do a far more creditable job. Or at least, I hope so!Things were also happening quite quickly, as I expected. Passing 1500' AGL I called blindly for climb thrust, not knowing exactly what setting was required, merely that it was probably required! Luckily my F/O handled that. I had briefed him to call '1000' to go to level off', but in the spirit of him acting only semi competently, he never did so at any time. At 3000' AGL, I began the acceleration to 210 KIAS, which is minimum clean (flaps up) speed. Passing 190 KIAS (Flap 1 manoeuvering speed), I called 'Flaps up'. IRL, the pilots in the B732 will not hear the flaps move at all. All that can be heard is the 'Ca-Click' of the flap lever being moved from one notch to the next - the tinmouse aircraft and panel have this wrong. The sound of the airflow also changes, becoming quite noticeably smoother.Apart from the sensitivity in pitch, which is not too bad during climbs and descents, things were actually going quite well. I remembered to call 'Transition Altitude, set 1013' at 8000', and just concentrated on the basics - keep my scan of the primary flight instruments going, don't get too focused on one aspect at the expense of others, and concentrate on relaxing and flying smoothly, with a careful eye on the correct attitudes on the Attitude Director Indicator (ADI, basically the artificial horizon). FL100 approached quite quickly, but I had been told the level off need only be initiated a few hundred feet before the target altitude, which of course turned out to be the case. This is due to the relatively small change in attitude required from the climb to the level flight attitude.Now the real challenge caused by the pitch sensitivity came to the fore. In the simulator, you have to hold PRECISELY the correct attitude the whole time - any change, and you'll be climbing or descending right away. And it's very sensitive, almost like it just can't settle into any one attitude. IRL, the aircraft seems more able to just settle into an attitude and hold it. The tinmouse aircraft actually does quite a good job here once again, possibly even better than the full motion sim! It's difficult to tell without having a proper yoke with the correct forces though, and MSFS's dismal gauge technology, which precludes having smooth movement from basic bitmap instruments doesn't help here at all - attitude is very important. I note with interest those new gauges from RealityXP here, and wish (I know, it's futile!) that MS would incorporate that technology into FS for general use.Another contributing problem here is that the trim in the real aircraft is quite quick to move. You have to just apply little touches of trim, and allow some time, more than I was used to of course, to see whether it had had the desired effect. Interestingly, I remember first flying Richard Probst's B727 panel, and being irritated with that loud clattering trim sound. I now know that that's exactly what it sounds like! And heaven help you if you leave the trim handle on the trim wheel extended. They say you only do it once, because it smacks you really, really hard on the knee. I know, I've only done it once!Nevertheless, I had levelled off at FL100. Time for some basic handling skill checks!....which will be in part 3.

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Thanks again for that pleasant reading and the insights.>> In Microsoft Flight Sim, take off rolls can sometimes be likened to a pinball bouncing down a pipe, since in MSFS there's no way to stop your rudder pedals from operating the tiller!That's indeed a pain. I just came across a new option in FSUIPC :2. A new axis control is added, for direct assignment in the Axis assignments tab, for a Steering Tiller. This uses the FS Rudder control, but can be calibrated separately (eg to be more responsive -- use the inverse S-shaped slope options). When on the ground and at any ground speed less than 60 knots (default -- adjustable by MaxSteerSpeed parameter in the INI), the actual FS rudder action is controlled by a blend of the tiller and rudder axis inputs. At low speed it is predominantly tiller, and as speed increases the tiller becomes gradually less effective and the rudder input more so. Above the MaxSteerSpeed, or in the air, the tiller has no effect. Since the slope function can be used in both directions (more/less responsive), it really sounds worth for some experimenting.Mike

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