(i) the notice of appeal; or (ii) the application for an appeal certificate; shall be as prescribed by rules of court. (4) Subsection (1) shall not affect the operation of any sentence of a court martial, other than a sentence of death. 81 Determination of appeal against conviction Subject to section eighty-two, on an appeal in terms of this Part against conviction the Appeal Court shall quash the conviction only if it thinks that the finding of the court martial is unreason able or is not justified— (a) having regard to the evidence; or (b) on the ground of a wrong decision on any question of law; or that on any ground there was a miscarriage of justice: Provided that the Appeal Court may, notwithstanding that it is of the opinion that the point raised in the a ppeal might be decided in favour of the appellant, dismiss the appeal if it considers that no substantial miscarriage of justice has actually accrued. 82 Powers of Appeal Court (1) If it appears to the Appeal Court that an appellant, though not properly convicted on some charge preferred against him before the court martial by which he was tried, was properly convicted on some other charge so preferred and if the sentence passed by the court martial on the appellant was not warranted for the offence of which he was convicted on the other charge, the Appeal Court shall pass on him, in substitution therefor, such sentence so warranted as it thinks proper. (2) Where an appellant has been convicted of an offence and the court martial by which he was tried could lawfully have found him guilty of some other offence and it appears to the Appeal Court that the court martial must have been satisfied of facts which prove him guilty of that other offence, the Appeal Court may, instead of allowing or dismissing the appeal, substitute for the finding of the court martial a finding of guilty of the other offence and pass on the appellant, in substitution for the sentence passed on him by the court martial, such sentence as it thinks proper, being a sentence warranted for the other offence but not being a sentence of greater severity than the sentence passed by the court martial. (3) Where an appellant has been convicted of an offence committed under circumstances involving the higher of two degrees of punishment and it appears to the Appeal Court that the court martial by which he was tried ought to have found him guilty of the offence as being committed under circumstances involving the lower degree of punishment, the Appeal Court may, instead of allowing or dismissing the appeal, substitute for the finding of the court martial a finding of guilty of the offence as being committed under circumstances involving the lower degree of punishment, and pass on the appellant, in substitution for the sentence passed on him by the court martial, such sentence as it thinks proper, being a sentence warranted for the offence specified in the substituted finding but not being a sentence of greater severity than the sentence passed by the court martial. (4) If it appears to the Appeal Court that the accused did the act or omission charged against him but was a mentally disordered or defective person at the time the act was done or the omission made so as not to be responsible according to law for his actions, the Appeal Court may set aside the sentence passed at the trial and order that the appellant be kept in custody in a civil prison and subsection (7) of section fifty -four shall thereafter apply, mutatis mutandis. (5) The period of any sentence passed by the Appeal Court under this section shall, unless the Appeal Court otherwise directs, begin to run from the time at which it would have begun to run if it had been passed in the proceedings from which the appeal is brought and such sentence shall be deemed, for the purposes of this Act, to be a sentence that has been confirmed. 83 Powers of Appeal Court to obtain further evidence (1) For the purposes of this Part, the Appeal Court may, if it thinks necessary or expedient in the interests of justice, do all or any of the following— (a) order the production of any document, exhibit or other thing connected with the proceedings, the production of which appears to it necessary for the determination of the case; (b) order the president of the court martial by which the appellant was tried or the person who officiated as judge advocate at the trial to furnish a written report— (i) setting forth the court’s statement of the facts found to have been proved and its reasons for judgment and sentence; and (ii) dealing with the grounds upon which the appeal is based; (c) order any witness who would have been a compellable witness at the trial to attend and be examined before the Appeal Court, whether he was or was not called at the trial, or order the examination of any such witness to be conducted in the manner required by rules of court before any person appointed by the Appeal Court for the purpose and allow the admission of any deposition so taken as evidence before the Appeal Court;